LIBRARY OF CONGRESS. 
QB*S 

©]|#jt + dxtpgng^i Ifs* 

shelf _.£_:: & 



UNITED STATES OF AMERICA. 



/ 



ASTRONOMY 



FOR BEGINNERS, 



IN THIRTY-TWO LESSONS, WITH ILLUSTRA TIONS. 



By FRANCIS FELLOWES, M. A. 



NEW YORK: 
JOHN WILEY & SONS, 

15 Astor Place. 



Copyright, 1885, by FRANCIS FELLOWES. 



/ 



M. H. Green. 

PRINTER, ELECTROTYPER AND BINDER, 

74 and 76 Beekvian Street, 

NEW YORK. 






PREFACE. 



This book is designed for beginners. — Instead, 
therefore, of beginning in the middle, or at the 
end, it begins at the beginning ; and seeking to 
avoid an indiscriminate blending of all things, 
treats of such things, and such only, as are suit- 
able to be set before beginners. 

It does not offer to the young learner, as his 
first lesson in Astronomy, any such positions as 
these : The Universe is infinite — the Sun is a 
vast globe 880,000 miles in diameter, placed in 
the centre of the Solar System, and dispensing 
light and heat to all the planets, which revolve 
round him in elliptical orbits — their radii vectores 
describing equal areas in equal times. Nor does 
it discourse upon the Laws of Kepler, nor descant 
upon the Centrifugal and Centripetal Forces, nor 
discuss the Properties of the Ellipse. If, in pre- 



IV PREFACE. 

paring a treatise for beginners, such things had 
entered into the plan of the author, he would 
have written in Arabic. 

The first thing to be done, in studying Astro- 
nomy, is to observe the Heavens, and to become 
familiar with the appearances which present them- 
selves there ; for without doing this it is impossi- 
ble to arrive at any proper understanding of the 
science. First of all, therefore, I have directed the 
attention of the pupil to the general form of the 
Heavens ; then to the situation, most remarkable 
appearances, motions, etc., of the sun — moon — 
planets — fixed stars, and comets — and, finally, I 
have given a brief view of the Solar System. 
Such I believe to be the natural order ; — it is the 
order which was followed in establishing the 
science — and necessary to be followed by those 
who would acquire any proper knowledge of it. 

But the attention of the learner has not been 
confined to appearances merely. As opportunity 
offered, remarks have been made and hints 
thrown out, calculated to show him the illusive 
nature of the scenery of the Heavens, and to lead 



PREFACE. V 

him to just notions of the real magnitudes, mo- 
tions, distances, and nature of the heavenly 
bodies. 

The work is not a compilation. The author's 
design was to place the science of Astronomy- 
fitted as it is to enlarge the understanding and 
elevate the moral feelings — within reach of be- 
ginners. For this end, no compilation would 
suffice. It was necessary to employ an arrange- 
ment — a style — and a manner entirely new. The 
designs for the engravings are many of them 
original, being expressly adapted to illustrate the 
simple, elementary ideas which it is the object of 
this book to inculcate. 

When the pupil has acquired these ideas, he 
will be prepared to advance to the study of larger 
and more difficult works. 

Francis Fellowes. 

Hartford, Conn., 

February, 1885. 



CONTENTS. 



LESSON PAGE 

I. — The Heavens . , i 

II. — The Sun— Daily Motion . 5 

III. —The Sun— Annual Motion , , . . 9 

.IV. — The Moon — Appearance and Motion , . . . 15 

V. — The New Moon and Half Moon t 19 

VI.— The Full Moon and Old Moon 22 

VII. — Eclipses of the Sun 28 

VIII. — Eclipses of the Moon and Occultation of Stars 36 

IX. — The Inferior Planets — Venus and Mercury, 39 

X. — The Superior Planets — Jupiter and Others 47 

XI. —The Asteroids 50 

XII.— The Planets are Worlds , 52 

XIII. — The Fixed Stars — Their Number, Names, Magnitude, 

Motion, and Distances 56 

XIV. — Division of the Heavens 61 

XV. — Stars of the First Magnitude 64 

XVI. —The Pole Star— The Great Dipper 67 

XVII. — Constellations always Visible 71 

XVIII. — Summer Constellations 77 



viii CONTENTS. 

LESSON PAGE- 

XIX. — Summer Constellations — Continued 80 

XX. — Winter Constellations 83 

XXI. — Winter Constellations — Continued 85 

XXII. — Winter Constellations — Continued go 

XXIII. — Constellations not Visible from the United States. ... 95 

XXIV.— New, Variable, and Double Stars 98 

XXV.— Colored Stars 103 

XXVI.— Nebula 105 

XXVII.— The Fixed Stars are Suns no 

XXVIII. —Comets 112 

XXIX.— The Solar System 117 

XXX. — The Solar System — Continued 121 

XXXI.— The Solar System— Continued 125 

XXXII. —History of Astronomy 132 



ASTRONOMY. 



LESSON FIRST. 

THE HEAVENS. 

i. You have all read, that in the beginning 
God created the Heavens and the Earth. I sup- 
pose you have studied Geography. Geography 
treats of the Earth. If you now wish to learn 
something about the Heavens, you must study 
Astronomy. Astronomy treats of the Heavens. 

2. The Heavens consist of the sky, and of the 
sun, moon, and stars, which seem to be placed 
within it. The earth, as you have learned, is 
round like a ball. The Heavens surround the 
Earth. We know this because the people, on all 
sides of it, can look up and behold them. If you 
should go to Europe, or to Asia, or to any other 
part of the earth, you could always see sky ; and 
in a clear night it would be a beautiful blue sky 
with stars. 

3. On the opposite page is a picture of the 



2 ASTRONOMY. 

Earth surrounded by the Heavens. Travellers 
tell us that when it is day on one side of the 
earth, it is night on the other side. On the light 
side of the picture, it is day ; on the other side, it 
is night. You see no stars represented on the 
light side. There are stars there as well as on the 
dark side, but on account of the sun's light, 
which spreads all over the sky, they cannot be 
seen. There are stars overhead in the day-time 
as well as in the night. We know this because 
the sun has been eclipsed, or darkened, in the day- 
time, and then the stars have appeared. On the 
dark side of the picture, where it is night, the 
stars are seen, shining through the darkness. — In 
the day-time, you cannot perceive the light of a 
candle, placed at some distance from you ; but in 
the night you can see the lights through the win- 
dows of very distant dwellings. So it is with the 
stars. 

4. You have all looked up to the sky on a clear 
evening. It looks like a beautiful blue vault, 
with thousands of stars set in it, all sparkling 
like diamonds. — The highest point in the sky ap- 
pears to be that which is right overhead. This 
point is called the Zenith. All around you, at 
the most distant limit to which the eye can reach, 
the sky seems to touch the ground, making as it 



THE HEAVENS. 3 

were a circle. This circle is called the Horizon. 
Horizon means boundary; it is the boundary of 
the sight, — you cannot look beyond it. 

5. We call certain points in the horizon, East, 
West, North, and South. East is near where the 
sun rises. West is near where he sets. If you 
stand with your back towards the sun at noon, 
your face will be towards the North; your back, 
towards the South; your right hand, towards the 
East; and your left hand, towards the West. 

6. The sun, moon, and stars, all appear to 
move in the sky. The moon appears very differ- 
ently at different times ; and the stars, although 
at first glance they may seem to be alike, have 
different degrees of brightness. Numerous as 
they are, men have given names to them all. 
They began to give names to them thousands of 
years ago. In one of the oldest books which we 
have, the Book of Job \ we find the names Arctu- 
rus, Pleiades, Orio7i. 

7. The most important things to be learned, in 
beginning to study Astronomy, are the names, 
appearance, positions, and motions, of the sun, 
moon, and stars. In some respects, Astronomy 
is like Geography. In studying Geography, you 
learn the appearance, names, and situation of 
places on the Earth ; in studying Astronomy, 



4 ASTRONOMY. 

you learn the appearance, names, and situation of 
objects in the Heavens. 

8. It will be of little use to you to study books 
on Astronomy, unless you go out and look at the 
Heavens for yourselves. Men first began to 
study Astronomy by observing the Heavens. 
They observed them a long time before any 
books on Astronomy could be written. The 
shepherds, on the plains of Babylon, were the 
first Astronomers. As they lay upon the ground, 
under the open sky, watching their flocks, they 
observed the stars, and thus learned Astronomy. 
— David, king of Israel, was once a shepherd ; and, 
as I think, while taking care of his flocks, used 
to observe the Heavens. Filled with admiration 
of their glory, he thinks how glorious He must 
be who made them. He says, "the Heavens 
declare the glory of God." Like David, observe 
the Heavens, and learn to adore their Maker. 



Who created the Heavens, and 
the Earth ? 

What science treats of the 
Earth ? 

What science treats of the Hea- 
vens ? 

What are the Heavens ? 

What is the shape of the Earth ? 

How do we know that the 
Heavens surround the Earth? 



QUESTIONS. 

3. What does the picture opposite 
to page first represent? 

How do we know that, when it 
is day on one side of the 
Earth, it is night on the other 
side? 

On which side of the picture is 
it day ? 

On which side is it night? 



THE SUN — DAILY MOTION. 



5 



Are there any stars in the sky, 

in the day-time ? 
How do you know this ? 
Why cannot the stars be seen 

in the day-time? 

4. How does the sky look in a 

clear evening? 
Which seems to be the highest 

point in the sky ? 
What is this point called ? 
What is the circle called which 

the sky seems to make, where 

it appears to touch the 

ground ? 
What does Horizon mean? 

5. What are East, West, North, 

and South ? 
Where is East? 
Where is West ? 
Where is North? 
Where is South? 

6. Do the sun, moon, and stars 

appear to move ? 



Which of these bodies appears 
very differently at different 
times? 

Do the stars all appear just 
alike ? 

In what respect are thev un* 

. like? 

Who have given names to the 
stars ? 

What names of stars are found 
in the Book of Job ? 

What are the most important 
things to be learned in begin- 
ning to study Astronomy ? 

Tell me some things in which 
Geography and Astronomy 
are alike ? 

How did men first begin to 
study Astronomy? 

Who were the first Astrono- 
mers? 

What king of Israel was once 
a shepherd and Astronomer ? 



LESSON SECOND. 



THE SUN— DAILY MOTION. 



i. The Sun seems to be the largest, brightest, 
and most powerful object which ever appears in 
the heavens. His light wakes men, and animals, 
and birds from their sleep, and renders the face 
of the earth visible ; while his warmth seems to 
impart life and activity to all things. He is so 



6 ASTRONOMY. 

powerful, it is no wonder that he should be called 
the king of day. The Bible says that God made 
the sun to rule over the day. 

2. The sun appears to have two motions ; a 
daily motion, and an annual motion. The daily 
motion is that which he seems to perform through 
the heavens every day. Although you have 
observed it many times, I will describe it, and 
then, perhaps, you will observe it more atten- 
tivelv. 

3. A short time before sunrise, you may see a 
few rose-colored streaks of light reaching up into 
the eastern sky, and separating from each other 
very much like your fingers, when you hold them 
up and open them wide. The Greeks used to im- 
agine them to be the fingers of a goddess, whom 
they called rosy-fingered Aurora. These rays 
become thicker and thicker, until the whole east- 
ern sky is of a rosy red. The light which appears 
before the sun rises, is called the Morning Twi- 
light. 

4. Soon the sun himself is seen, just where the 
eastern sky seems to touch the ground. He is 
now said to be in the horizon. He looks large, 
round, and of a reddish color. The rising sun is 
a glorious object to behold. He is compared, in 
the Bible, to a bridegroom coming out of his 



THE SUN — DAILY MOTION. 7 

chamber. You will understand this, when you 
are informed that in eastern countries, the bride- 
groom came out of his chamber in the night, in a 
dress adorned with gold and precious stones, re- 
flecting the light of many torches, borne by his 
friends, and went forth to meet the bride. Just 
so the sun comes up, arrayed. in his glory. 

5. The sun seems to ascend into the sky always 
a little south of you, until he has come to the 
highest point to which he can reach. He is then 
said to be on the meridian, and is exactly south 
•of you. He has now finished just one half of his 
daily journey, and it is said to be mid-day, or 
noon. 

6. As soon as the sun reaches the meridian, he 
begins to descend. This he continues to do, 
until you see him in the western horizon, just 
opposite to where he was when he rose. He has 
now finished the other half of his daily journey, 
and soon disappears. 

7. After the sun disappears below the horizon, 
his rays continue for a while to come up into our 
sky. The light which appears in the evening, 
after the sun sets, is called the Evening Twilight. 

8. I have now described to you the daily 
motion of the sun. You think, perhaps, that the 
sun really moves. He appears to move, but you 



8 ASTRONOMY. 

must not, from this, conclude that he does move. 
When you ride in a coach, or sail down a river in 
a boat, if you fix your eyes upon the trees and 
other objects on the earth, they seem to move, 
but you do not conclude from this, that they do 
move. It is the coach, or the boat, in which you 
are, that moves, and this makes the objects, on 
which you fix your eyes, appear to move. If 
we suppose that the sun remains perfectly still, 
and that the earth, suspended in the heavens, 
turns round, presenting its sides one after another, 
to the sun, the sun will appear to move just as 
he now does. 

9. Day and Night. — The sun's daily motion, 
whether real or apparent, makes day and night 
It is very plain that if the sun were always in 
the sky above us, we should always have day ; 
and that if he were always in the sky on the other 
side of the earth, we should always have night. 
We know that when the sun disappears from our 
sky, he appears in the sky on the other side of 
the earth ; and that when we see him, he cannot 
be seen there, because people who have been 
there tell us so. 

Look at the picture opposite to page first, 
and you will see day represented on one side of 
the earth, and night on the other. 



THE SUN — ANNUAL MOTION. 



QUESTIONS. 



Which seems to be the largest, 
brighest, and most powerful 
of all the heavenly bodies ? 

How many motions does the 
sun appear to have ? 

What are they called ? 

What is the sun's daily motion ? 

What is the color of the light 
which first appears in the 
morning? 

How do the streaks of light 
reach up into the sky ? 

What did the Greeks use to im- 
agine them to be ? 

What is the morning twilight ? 

When the sun first appears in 
the morning, where is he 
said to be ? 

How does the rising sun look? 

To what is he compared in the 
Bible ? 

Explain this. 

Which way from you is the sun 
as he ascends into the sky ? 

When the sun is highest, where 
is he said to be ? 



Which way from you is he at 

that time ? 
How much of his daily journey 

has he then finished ? 
When the sun has reached the 

meridian, which way does he 

begin to go ? 
How much of his daily journey 

has he finished when he ap- 
pears in the western horizon ? 
What is the evening twilight? 
Is it certain that the sun really 

moves ? 
Tell me some instances in 

which things appear to move,, 
that do not. 
What may make the sun appear 

to move, although perfectly 

still ? 
What makes day and night ? 
Where does the sun go, when 

he disappears from our sky ? 
When we see the sun, can he 

be seen on the other side of 

the earth ? 
How do we know this ? 



LESSON THIRD. 

THE SUN— ANNUAL MOTION. 

i. The sun does not always rise and set in the 
same points of the horizon. 

In summer, he rises and sets farther north, 
and in winter, farther south. Have you not ob- 



IO ASTRONOMY. 

served, that he seems to be farther south of us, 
in winter, than in summer? In winter, his rays 
come to us, from the south, in a slanting direc- 
tion ; but in summer, he appears to pass through 
our sky more directly overhead, and his rays come 
more directly down upon us. 

2. The sun rises and sets farthest north on 
the 21st day of June. This is the longest day in 
the year. On this day, the sun has the longest 
distance to go through our sky. Hence he is 
the longest time above our horizon. 

The sun rises and sets farthest south on the 
2 1 st day of December. This is the shortest day 
in the year On this day, the sun has the short- 
est distance to go through our sky. Hence he is 
the shortest time above our horizon. 

After the 21st day of December, he rises and 
sets farther and farther north, until the 21st day 
of June, when he begins to rise and set farther 
and farther south again. 

Two days in the year, the sun rises exactly in 
the east and sets exactly in the west. These days 
are the 21st day of March and the 21st day of 
September. The day and night are then equal. 
We know all this from long observation. 

3. Thus the sun seems to be moving, the 
whole year, from north to south, and from south 



THE SUN — ANNUAL MOTION. II 

to north again. This motion is called his annual, 
ox yearly motion. It is not so perceptible as his 
daily motion, but you may easily discover it. If 
you notice a tree, a building, or some other ob- 
ject in the direction of the rising or setting sun, 
you will see, after several days, that he appears to 
have moved. 

4. I told you, in the last lesson, you must not 
conclude that the sun, because he seems to move 
across the heavens every day, really does move. 
Neither must you conclude that he really moves 
north and south every year, because he seems to 
do so. The motion of the earth would make 
him appear to move. 

5. The annual motion of the sun makes the 
days and nights of unequal length. You know 
that the days are much shorter in winter than 
they are in summer ; and the nights, much longer. 
The reason of this is very plain. Look up at the 
sky, and you will see that it does not appear to 
be so far across it, south of you, as it does right 
overhead. Now, it is the sun passing through 
our sky, that makes the day. In winter he passes 
through it quite south of us, and has less distance 
to go. It therefore takes a less number of hours. 
In other words, the sun is in our sky a shorter 
time ; the days are shorter, and the nights longer. 



12 ASTRONOMY. 

6. Winter and Summer. — The annual motion 
of the sun also makes Winter and Summer. It 
does this in several ways. Since in winter the 
days are shorter, the sun's heat comes to us a 
shorter time than in summer, and in the long 
nights, the earth has a longer time to cool. This 
is one thing which makes the difference between 
winter and summer. I will now tell you another. 

7. When the sun is far south of us, as he is in 
winter, his rays fall upon the earth slantingly, 
and for this reason, are more scattered than they 
are in summer, when the sun is overhead, and his 
rays fall straight down upon us. On page 13, is a 
picture representing the sun's rays as they fall 
upon us in winter, and in summer. Look at the 
picture, and you will see that in winter they are 
more scattered than in summer. For this rea- 
son, they do not feel so hot to you. 

If you should put some coals of fire into a lit- 
tle pan and hold your hand over them, they 
would feel much hotter than the same coals would 
if scattered about in a larger pan. So it is with 
the sun's rays. Have you ever seen a sun-glass? 
When a sun-glass is held up to the sun, his rays, 
in passing through it, are brought closer together, 
and on this account, feel very hot to the hand, 
and will even set paper on fire. 



THE SUN — ANNUAL MOTION. 



13 



8 There is still another reason why we have 
less' heat in winter than in summer. The earth, 
you know, is surrounded by the air or atmos- 
phere, through which the rays of the sun have to 



Summer rays 



Winter rays. 




travel before they can reach us. It has been 
found that some of the sun's rays which enter 
the atmosphere get lost on the way. I suppose 
the atmosphere swallows them up. 



14 



ASTRONOMY. 



Now look on the picture, and you will see that 
the winter rays have to travel a greater distance 
through the atmosphere than the summer rays. 
The atmosphere through which they travel is also 
nearer the earth, and on this account, thicker. 
For these reasons, more of them are swallowed 
up, and never come to the earth. Of ten thou- 
sand rays which enter the atmosphere when the 
sun is in the horizon, it has been computed, that 
only five reach the earth. 

I have now explained to you the principal 
causes of Winter and Summer. 



QUESTIONS. 



i. Does the sun always rise and 

set in the same points of the 

horizon ? 
When does he rise and set far- 
ther north ? 
When farther south ? 
In what direction do the winter 

rays come to us ? 
In what direction, the summer 

rays? 
2. On what day" of the year does 

the sun rise and set farthest 

north ? 
On what day farthest south ? 
After the 21st of December, 

which way does the sun 

seem to move ? 
Which way after the 21st of 

June ? 



How many days in the year 

does he rise exactly in the 

east, and set exactly in the 

west ? 
What days are these? 
When are the days and nights 

of equal length ? 
What is the motion of the sun, 

north and south, called ? 
Is it as perceptible as his daily 

motion ? 
How may you easily discover 

it? 
Do you certainly know that the 

sun moves north and south ? 
What might make him appear 

to move in this direction ? 
What makes the days and 

nights of unequal length ? 



THE MOON — APPEARANCE AND MOTION. 



15 



7- 



In what season are the days 
shortest, and the nights long- 
est? 

Explain the reason of this? 

What makes winter and sum- 
mer ? 

When has the earth a shorter 
time to become hot by day, 
and a longer time to cool by 
night ? 

How do the winter rays strike 
the earth ? 

Are they more or less scattered 
than the summer rays ? 

Which feel the hottest, scat- 



tered rays, or the same num- 
ber of rays close together ? 

What must the sun's rays 
travel through, before they 
can reach us ? 

Do all the rays which enter the 
atmosphere, reach the earth ? 

What becomes of some of them? 

Why do less rays reach the 
earth in winter than in sum- 
mer ? 

Of ten thousand rays which 
enter the atmosphere when 
the sun is in the horizon, 
how many reach the earth ? 



LESSON FOURTH. 



THE MOON— APPEARANCE AND MOTION. 

i. The Moon is the most beautiful object 
which we ever behold in the sky. "Every one 
admires the moon. Even young children think 
her so beautiful that sometimes they cry, because 
they cannot reach their little hands up into the 
sky, and pull her down to them. How dark the 
nights would be, if there were no moon to spread 
her soft and silvery light over the face of the 
earth. 

2. The sun, all-powerful and splendid as he is, 
is sometimes called a king. The moon, less 
powerful and splendid, but more lovely and beau- 



1 6 ASTRONOMY. 

tiful, is sometimes called a queen. The Bible 
says that God created the moon to rule over the 
night. This means that she seems to be the 
largest of all the bodies seen in the sky by night, 
and has power to chase away the darkness. Here 
is a picture of the moon's phases. 

Old. Full. Gibbous. 






3. Phases means appearances. The phases of 
the moon are her different appearances. They 
are a most wonderful thing. The sun and the 
stars always preserve very nearly the same ap- 
pearance, but the moon is almost continually 
changing. Sometimes, she looks like a bow of 
light hung up in the sky. Then, after a few days, 
she resembles the half of a new cheese, which 
seems to increase every night, on the straight 
side, growing rounder and rounder, until she 
seems perfectly round. The most remarkable 
phases of the moon are five in number. You 
see them represented on the picture. Their 
names are new, half, gibbous, full, and old. 



THE MOON — APPEARANCE AND MOTION. 1 7 

4. The moon has some other remarkable ap- 
pearances. She does not seem of a silvery white- 
ness all over ; some spots appear dark. Once, 
astronomers supposed that the moon's surface, 
like the earth's, consists of land and water. The 
bright parts, they thought were land, and the dark 
spots, water. Recent observations seem to prove 
that, while there are many mountains and volca- 
noes on the moon, there is no water. 

5. The moon, like the sun, appears to have 
motion. Two of her motions are very percepti- 
ble. One of them is from east to west. This 
motion you can see every night, when she is visi- 
ble. If you observe her at any time, and then 
an hour or two afterwards observe her again, you 
will see very clearly that she seems to have moved 
towards the west. If you observe her long 
enough, you will see her set, like the sun, below 
the western horizon. The earth turning round 
like a great ball, from west to east, would make 
the moon appear to move from east to west. 
But you will ask me, Where does the moon go, 
when she sets ? She is in the sky on the other 
side of the earth. 

6. The other motion of the moon is from west 
to east. You cannot perceive this motion by 
looking at her only one night. If you wish to> 



18 



ASTRONOMY. 



perceive it, you must observe her several nights 
in succession. You will then see that every 
night she appears farther and farther towards the 
east, when she first becomes visible. I think 
that the moon really moves through the sky 
around the earth, from west to east. I have rea- 
sons for believing that it is not the motion of the 
earth which, in this case, makes her appear to 
move. But I cannot explain them to you now. 



QUESTIONS. 



1. What is the most beautiful ob- 
, ject which we" ever behold in 

the sky ? 
How do we know that even 
young children admire her 
beauty ? 

2. What does the Bible say that 

the moon was created to rule 
over? 
What is meant by the moon 
ruling over the night ? 

3. What does the word phases 

mean? 
What are the moon's phases ? 
What different appearances has 

the moon ? 
How many in number are her 

most remarkable phases ? 
What are they called ? 

4. What other remarkable appear- 

ances has the moon ? 



What did astronomers once 
think the bright parts to be ? 

What did they think the dark 
spots were ? 

What do recent observations 
seem to prove ? 

How many motions of the 
moon are very easily per- 
ceived? 

Which way does the moon ap- 
pear to move every night ? 

Where does she go when she 
sets ? 

Which way is the other motion 
of the moon ? 

Can you see this motion on 
any one night ? 

What must you do if you wish 
to perceive it ? 



THE NEW MOON AND HALF MOON. 



19 



LESSON FIFTH. 

THE NEW MOON AND HALF MOON. 

i. Here is a picture of the New Moon, 




New Moon. 



The New Moon appears in the west, when the 
sun is setting. It is a little way above the sun. 
You can see the new moon but a very short 
time. It seems to be going down lower and 
lower, and soon disappears below the western 
horizon. 



20 ASTRONOMY. 

2. There was once in Judea a beautiful cus- 
tom of announcing the appearance of the new 
moon. Some persons used to keep watch for it, 
and, as soon as they saw it, they came to Jeru- 
salem to tell the rulers. The rulers sent a man 
with a bundle of straw or brush to the top of the 
Mount of Olives, which was near Jerusalem. 
There the man set his bundle on fire, and kept 
waving it backward and forward. As soon as 
the people saw it, they made similar fires on the 
surrounding hills, which other people imitated, 
until the whole country blazed with the joyful 
signal. All this was done to tell the people when 
the holidays would come. The holidays hap- 
pened a certain number of days after new moon. 
Some nations used to observe the time of new 
moon as an occasion of feasting and rejoicing. 
Every one is pleased to behold the moon when 
she returns to gladden the earth with her light. 

3. The moon continues to increase, appearing 
farther and farther east every night, at sunset, and 
in about a week she appears on the meridian, a 
Half Moon. On the next page is a picture of the 
Half Moon. 

You see the sun setting in the west, and the 
Half Moon on the meridian. If you observe it, 
in the sky, a little while, you will see that it 



HALF MOON. 



21 



seems to be moving towards the west. Can you 
tell me at what time it will go down ? It takes 




Half Moon. 

the sun half a day to go the same distance. It 
will, then, take the moon half the night. It will 
set at midnight. 

QUESTIONS. 



2. 



Where and when does the new 
moon appear? 

How far does it seem above 
the sun ? 

How long can you see the new 
moon? 

Which way does it seem to be 
going ? 

Where does it disappear ? 

What beautiful custom of an- 
nouncing the appearance of 
the new moon once existed 
in Judea ? 



What was this done for? 
How long a time is it from new 

moon to half moon ? 
Which way does the moon 

seem to be moving during 

this time ? 
Where does the half moon ap- 
pear at sunset ? 
Which way does it seem to be 

moving? 
At what hour will it set ? 



22 



ASTRONOMY. 



LESSON SIXTH. 

THE FULL MOON, AND OLD MOON. 

i. The moon still continues to increase, ap- 
pearing farther and farther toward the east every 




Full Moon. 

night at sunset. When her eastern side begins 
to look roundish, she is said to appear gibbous. 

2. In about two weeks from new moon, you 
see the Full Moon, rising in the east, while the 
sun is setting in the west. Here is a picture of 
the Full Moon. 



THE FULL MOON, AND OLD MOON. 



23 



You have often seen the full moon 
above the horizon, round and large, like the suil 
The full moon rises when the sun sets, and sets 
when the sun rises. It shines all night. 

3. The moon, after her full, rises after sunset, 
and later and later every night. She now seems 
to decrease, on her western side, until she ap- 
pears first a gibbous, then a half moon, and in 




Old Moon. 

about a week from the time of her full, again 
looks like a bow of light suspended in the sky. 
She seems almost worn out, and is for this reason 
called Old Moon. Here is a picture of the Old 
Moon. You see it in the east, just above the 
rising sun. 



24 ASTRONOMY. 

4. The old moon and the new moon look just 
alike. But the new moon, you remember, ap- 
pears in the evening, just above the setting sun, 
and its horns are turned towards the east. The 
old moon appears in the morning, just above the 
rising sun, and its horns are turned towards the 
west. Will you remember that the round side 
of the moon is always towards the sun ? 

5. The old moon is in the sky over our heads in 
the day-time. I have seen her in the sky about 
the middle of the afternoon. A few days before 
I wrote this lesson, I saw her at this time. A 
little boy about six years old first observed her, 
and showed her to me. The air was a little 
hazy, and the sun's light somewhat darkened. — - 
But where is the moon when we cannot see her 
in the evening sky? Like the sun when he is 
gone down, she is in the sky on the other side of 
the earth. The people there can see her. God 
takes care of them as well as of us. He gives 
them the moon, a part of the time, and us, a 
part. 

6. I have now told you about all the different 
phases, or appearances, which the moon has. Are 
they not a very wonderful thing ? Have you 
never wondered what it can be that makes 
them ? 



THE FULL MOON, AND OLD MOON. 2$ 

7. I will now tell you. The moon is a great 
dark ball. She has no light of her own ; it is all 
borrowed from the sun. The sun's light falls 
upon her surface, and bounds off until it strikes 
the earth. Sometimes it comes to us through 
the dark sky of night, and makes the moon 
visible. 

8. The moon goes round the earth from west 
to east once a month, always presenting one side 
to the sun. You remember that we saw her 
moving from west to east, day after day, as we 
watched her progress from new moon to full 
moon. The side towards the sun is light, and. 
the other side, dark. 

9. Now look on the picture on the next page, 
and I will show you what makes the moon's phases. 

You see the moori represented here, just as 
she appears in different parts of her course around 
the earth. In one place she is right between the 
earth and the sun. Here her dark side is towards 
us, and we cannot see her at all. As she moves 
up, her light side begins to be towards us, and we 
see that little bow of light which we call new 
moon. As she moves forward, her light side 
turns towards us more and more, until she has 
completed half her journey round the earth. 
Now the whole of her light side is towards us, 



26 



ASTRONOMY. 



and she appears full Look on the picture, and 
you will perceive that from new moon to full 
moon is half way round the earth. 




Moon going round the Earth. 



io. Now the light side begins to turn from us, 
and we see the moon decreasing, during the other 
half of her course, just as she before increased. 
At length she becomes a slender bow of light 
again. She seems almost worn out, and we call 
her old moon. Finally, coming to the spot from 
which she started, between the earth and the sun, 
her whole enlightened side is again turned from 
us, and she disappears. Thus the moon travels 



THE FULL MOON, AND OLD MOON. 



27 



round the earth every month, showing to the in- 
habitants, on its different sides, her wonderful 
phases, cheering them with her light, and like 
Him who made her and placed her in the sky, 
seems never weary in well-doing. 



QUESTIONS. 



1. As the moon increases, which 

way does she seem to have 
moved every night? 
When is she said to appear 
gibbous ? 

2. How many weeks from new 

moon to full moon ? 
Where does the full moon first 

appear ? 
When does the full moon set? 
How much of the night does it 

shine? 

3. Does the moon rise earlier, or 

later, every night after her 
full ? 

Which side now begins to de- 
crease ? 

How long before the moon 
again looks like a bow ? 

What is she now called ? 

4. At what time of day, and where, 

does the new moon appear? 
Which way are its horns turned? 
At what time of day, and where, 

does the old moon appear? 
Which way are its horns turned? 
Which way is the round side 

of the moon always turned ? 

5. Where is the old moon in the 

day-time ? 



Where is the moon gone, when 

we cannot see her, in the 

night? 
Have you never wondered what 

makes the moon's phases ? 
What is the shape and color of 

the moon ? 
Where does she get her light ? 
What becomes of the sun's 

light when it falls on her 

surface ? 
What makes the moon visible 

to us? 
How often does the moon go 

round the earth ? 
Which way does she move ? 
As she thus goes round the 

earth, which side is light, and 

which side dark? 
Now look on the picture, page 
26. How is the moon repre- 
sented there ? 
Point to her when right be- 
tween the sun and the earth. 
Why do we not see her when 

she is there ? 
Point to the new moon. 
What makes the new moon ? 
Point to the half moon. 



28 



ASTRONOMY. 



How much of the light side is 

now towards the earth ? 
How much of her journey has 

the moon now completed ? 
Point to the gibbous moon. 
Point to the full moon. 
What makes the full moon ? 
How much of her journey has 

the moon now completed ? 
10. Which way does the moon's 

light side now begin to turn ? 



What phase does the moon 

have next after full moon ? 
Point to the gibbous moon 

again. 
What phase does she have 

next? 
What phase next? 
Why do we call this phase old 

moon ? 
Show me, on the picture, where 

the moon disappears. 



LESSON SEVENTH. 



ECLIPSES OF THE SUN. 

i. Eclipses are the most remarkable appear- 
ances ever seen in the heavens. 

To see the unclouded sun suddenly grow dark 
strikes people who do not understand the cause, 
with fear and amazement. All nature seems sud- 
denly shivering with a chill. The moon and stars 
appear, the birds and animals seek their resting- 
places. In broad daylight, Night suddenly re- 
sumes her reign, covers the heavens with her dark 
mantle, bespangled with stars, and marked with 
the strange and wonderful appearances of the 
eclipse. 

2. This darkening of the sun is called a Solar 



ECLIPSES OF THE SUN. 29 

Eclipse. Eclipse means failure, or extinction, of 
light. Thus, blind Milton says: 

" Light, the prime work of God, to me is extinct, 
Irrecoverably dark, total eclipse." 

3. A heavenly body is eclipsed when it is dark- 
ened by a dark body coming between it and the 



_ == ^^^ 


- \ mmS^ 


--SL. 




% SUN pT^ 


^m^^^lkMb=^^ 


^ yfe^^^^ ^ 




iB^s^ ^^^===- = 




■== ~ = 




^=^Ei/ ■ r - 




= -— ■=. : 




^^^=^=z=fi3=lk ■ — 









Eclipse of the Sun. 

observer. Thus the sun is eclipsed when the 
moon comes between him and the earth. 

4. To understand this, you must imagine the 
sun to be -fixed as a centre, while the earth re- 
volves around him, in a great path, or orbit, and 
the moon revolves around the earth in a small 
orbit. Look at the above figure, and you will 



30 ASTRONOMY. 

see that the moon, in her revolution around the 
earth, will sometimes come between the earth and 
the sun. 

When this happens, the moon, being a dark 
body, will prevent so much of the sun's light, as 
strikes her, from coming to the earth. In other 
words, the moon will cast a shadow towards the 
sun, covering more or less of his disk. 

5. Disk, in astronomy, you must remember, 
means the /ace, or flat surface, of a heavenly body, 
as it appears to us. The sun, moon, and planets, 
you know, are shaped like a globe or ball, but 
owing to their distance from us, we cannot see 
their shape. We see only so much of their sur- 
face as is towards us, and this surface, on account 
of the distance, appears flat. This flat surface is 
what astronomers call the disk. Thus they say, 
the disk of the sun, the disk of the moon, the 
disk of Jupiter, and so on of other planets. 

6. A solar eclipse never occurs except when 
the moon is new, because the moon is never be- 
tween the sun and the earth except when she is 
new. Look at the figure on page 19, and you will 
see the new moon just above the horizon, be- 
tween the earth and the setting sun. 

But eclipses of the sun do not occur at every 
new moon, because the moon is not always in the 



ECLIPSES OF THE SUN. 3 1 

right position to obscure the sun every time she 
is new. 

7. An eclipse of the sun always begins on the 
western, and passes off on the eastern, side of his 
disk. You will observe this whenever you look 
at a solar eclipse. This is because the moon, in 
her revolution around the earth, comes between 
the western side of the sun and the earth first. 

8. There cannot be more than five, nor less 
than two, solar eclipses in any one year. This 
is because the moon never comes between the 
earth and the sun, in the right points of her orbit, 
to darken the sun more than five times in a year, 
and always comes into such points at least twice 
in a year. Astronomers have ascertained this by 
calculation and observation. 

9. Solar eclipses are either total, annular, or 
partial. When the eclipse is total, the sun's 
Avhole disk is obscured. When it is annular, 
there is left a rim or border of light quite around 
the outer edge of his disk, shaped like a ring. 
Hence the eclipse is called annular, which word 
means ring-shaped. When the eclipse is partial, 
only a part of the disk is obscured. In a total 
solar eclipse, total darkness never lasts more than 
seven or eight minutes. 

10. For the purpose of measuring the extent 



32 



ASTRONOMY. 




Total Eclipse of the Sun. 



ECLIPSES OF THE SUN. 33 

of partial eclipses, astronomers divide the disk 
into twelve equal parts, called digits. 

You read in the almanacs, the sun will be 
eclipsed, or the moon will be eclipsed, so many 
digits. By keeping in mind that a digit is one 
twelfth part of the whole disk, you will know 
the extent of the eclipse, that is, how much of 
the disk is obscured. Thus, if the sun be eclipsed 
six digits, one half his disk is obscured. 

11. The figure on page 32 represents a total 
solar eclipse. 

When you observe such an eclipse in the hea- 
vens, you will see a white silvery rim quite around 
the darkened disk of the sun, from which there 
shoot forth rose-colored protuberances of differ- 
ent heights. 

12. This appearance is caused by matter sur- 
rounding the body of the sun. When he is 
shining, you cannot see it. But when he is totally 
eclipsed, so as to appear a mere black spot, then 
it becomes visible. 

The following figure represents an annular 
eclipse of the sun. You will observe a rim or 
border of light quite around the sun's disk, but 
no protuberances. 

Observe that the ring in an annular eclipse, is 
on the outer edge of the sun's disk, and is a part 



34 



ASTRONOMY. 




Annular Eclipse of the Sun. 



ECLIPSES OF THE SUN. 



35 



of the disk, while the rim, in a total eclipse, is 
outside of the disk, and is no part of it. 

QUESTIONS. 



1. What remarkable appearances 

accompany an eclipse of the 
sun ? 

2. What does the word eclipse 

mean ? 
What is a solar eclipse ? 

3. When is a heavenly body 

eclipsed ? 
What dark body comes be- 
tween the sun and the earth 
when the sun is eclipsed ? 

4. Look at the figure on page 29, 

and explain how the moon 
eclipses the sun. 

5. What is the meaning of the 

word disk ? 
Why is it that we can see only 
the face, or disk, of the sun. 
moon, and planets? 

6. At what phase of the moon do 

solar eclipses always occur? 
Why cannot a solar eclipse 

occur at any other time ? 
Look at the picture on page 19. 

and point out the position of 

the moon when new. 
Do eclipses of the sun occur at 

every new moon? 
Why not? 

7. On which side of the sun's disk 

do eclipses of the sun begin ? 
Why? 

8. How many solar eclipses may 

there be in a year ? 
How many must there be ? 
Why is this ? 



How have astronomers ascer- 
tained this to be true ? 
9. Name the three classes of 

solar eclipses. 
When is a solar eclipse total ? 
When is it annular ? 
When is it partial ? 
What does the word annular 

mean ? 
Why is an annular eclipse so 

called ? 
When the eclipse is neither 

total nor annular, what is it ? 
In a total solar eclipse, how 

long may the total darkness 

last? 

10. How do astronomers divide 

the disk for the purpose of 
measuring eclipses ? 
If the sun is eclipsed six digits, 
how much of his disk is 
obscured ? 

11. Describe the appearance of a 

total solar eclipse, as repre- 
sented in the figure on page 
32. 

12. What is the cause of this ap- 

pearance ? 
Describe the appearance of an 
annular eclipse, as repre- 
sented by the figure on page 

34- 
What is the difference between 
the position of the rim of 
light, in an annular eclipse, 
and the rim, in a total eclipse? 



36 



ASTRONOMY. 



LESSON EIGHTH. 

ECLIPSES OF THE MOON, AND OCCULTATION OF 
STARS. 

i. Eclipses of the moon are caused by the 
earth, in its revolution in its orbit around the sun, 
coming between the moon and the sun, as in the 
following figure. 



- = 1 






^^^^^^= 






W sun r ^^ 


Iearw - 


= 1 


Lai^ t- ,. , 


/ - 





Eclipse of the Moon. 

2. An eclipse of the moon can never be annu- 
lar, since the earth is larger than the moon, and 



ECLIPSES OF THE MOON. 37 

is capable of obscuring the moon's entire disk. 
An eclipse of the moon must therefore be either 
total or partial, according as the earth, in its exact 
position between the moon and the sun, darkens 
the whole, or more or less, of the moon's disk. 

3. An eclipse of the moon can never take 
place except when the moon is full, since at no 
other time is the earth between her and the sun. 
Look at the picture of the full moon, page 22, 
and you will see her in the east, while the sun is 
in the west, and the earth between them. 

4. If you will observe eclipses of the moon, 
you will see that they always begin on the eastern 
part, and end on the western part, of her disk. 
This is because the moon moves from west to 
east. You will also see that her disk is not 
wholly obscured, but seems to be of a reddish 
color. This is because some of the sun's rays, 
instead of being intercepted by the earth, are 
bent out of their course by the atmosphere, and 
fall on the moon's disk. 

5. You will wonder when you learn that 
astronomers can tell, hundreds of years before- 
hand, when eclipses will happen. They can tell 
with certainty, and within a minute of the exact 
time. They can also tell whether the eclipse will 
be total, annular, or partial, and if partial, just 



38 ASTRONOMY. 

how much of the disk will be eclipsed. They 
can also go back and calculate eclipses that have 
happened, and tell the exact time when they 
happened. 

You will scarcely be able to understand, now, 
how astronomers can do this, but as you advance 
in the study of Astronomy, you will be able not 
only to understand it, but to do it. 

6. Occultation. — Stars and planets which lie 
in that part of the heavens in which the moon 
moves may be concealed by the moon coming 
between them and the earth. This concealment 
is called an Occultation, Occultation means con- 
cealment. 

When an occultation occurs, you will see the 
star or planet near the edge of the moon. 
Suddenly the moon will pass over it and conceal 
it from your sight until, in a short time, it 
emerges from beneath the moon's dislt, and shines 
again with its usual splendor. 

7. Also, one star or planet may occult another 
star or planet. 

QUESTIONS. 



1. What causes eclipses of the 

moon ? 

Look at the figure on page 36, 

and explain how the earth 

causes eclipses of the moon. 



Can an eclipse of the moon 

ever be annular ? 
Why not ? 
If the earth comes between the 

moon and the sun, so as to 



THE PLANETS — VENUS AND MERCURY. 



39 



darken the moon's whole 
disk, what will the eclipse be ? 
If the earth comes between the 
moon and the sun, so as to 
darken only a part of the 
moon's disk, what will the 
eclipse be ? 

3. At what phase of the moon 

can an eclipse of the moon 
take place ? 

Why cannot an eclipse of the 
moon occur at any time ex- 
cept when the moon is full ? 

Look at the figure on page 22, 
and point out the position of 
the earth, as it respects the 
sun, when the moon is full. 

4. On which side of the disk do 

eclipses of the moon begin ? 
On which side do they end ? 
Why is this ? 
In a lunar eclipse, is the disk 

wholly obscured ? 



Of what color does the disk ap- 
pear to be? 
Why is this ? 

5. What can astronomers calcu- 

late and predict in regard to 
eclipses ? 

6. What is the meaning of the 

word occidtation ? 
What heavenly bodies may be 

occulted or concealed by 

others. 
What heavenly body occults 

stars and planets ? 
In what part of the heavens 

must stars or planets be in 

order to be occulted by the 

moon ? 

7. Are there any other heavenly 

bodies, besides the moon, 
which occult others ? 

What are they ? 

What heavenly bodies do they 
occult ? 



LESSON NINTH. 

THE PLANETS— VENUS AND MERCURY. 

1. I have told you about the sun and moon. 
I shall now tell you about the stars. There are 
two kinds of stars. 

2. Most of the stars move across the heavens 
like a great army of soldiers marching. They 
seem to keep time, being always at the same 



40 ASTRONOMY. 

distance, and in the same place, with regard to 
each other. Such stars are called Fixed Stars. 

3. There are a few stars which seem to wander 
to and fro in the sky like a sentinel on guard. 
These are called Planets. The word planet 
means wanderer. 

4. The brightest and most beautiful of all the 
stars is the planet Venus. You have all seen her 
in the western sky, just after sunset. She is the 
first star which appears. 

"The vestal light of eve came on, 

And silvered tree, and tower, and spire, 
And in the warm blue sky there shone 
A gem of pure and living fire. 

M The boy one wondering moment eyed 
The bright thing shining clear and far, 
Then caught his father's hand, and cried, 
1 Look! father, God has made a star J " 

5. This star was Venus. She appeared so 
beautiful, the first thought of the little boy was 
that God made her. She shines with a steady, 
silvery light, like the moon. She does not twin- 
kle like the fixed stars. She is the only star 
which has been seen, with the naked eye, in the 
day-time. 

6. The motions of Venus are very wonderful. 
There is only one star, among the thousands which 



THE PLANETS — VENUS AND MERCURY. 



41 



spangle the sky, whose motions are like hers. 
Observe this picture attentively, while I describe 
them. 




East. 



Venus. 



West. 



7. For about ten months Venus is seen in the 
evening sky, just after sunset. She is then 
called the Evening Star. The poets sometimes 
call her Hesperus. Thus Milton says: 

" Hesperus, that led 
The starry host, rode brightest." 

When she first becomes evening star, she ap- 
pears where you see her on the picture, a little 
way above the western horizon, and near where 
the new moon appears. Like the new moon, 



42 ASTRONOMY. 

she seems to be moving west, and soon goes 
down. This motion may be perceived every 
evening when she is visible. You must not con- 
clude that it is a real motion. The motion of 
the earth from west to east is sufficient to make 
Venus, like the sun, appear to move in the oppo- 
site direction. 

8. But Venus has another motion much more 
curious. You must watch her evening after 
evening, if you wish to perceive it. Observe 
some star near her, and after a while you will 
see that Venus appears to have moved away 
from it towards the east. See her in the second 
highest place on the picture. 

9. If you continue to observe Venus, you will 
see that she appears farther and farther east, and 
higher and higher up, until she gets about half 
way up to the highest point of the sky. See her 
represented here on the picture. Now she seems 
stationary or still, for a time. 

10. Soon she begins to move again, but it is 
towards the west. She appears to be going back. 
She continues to do so week after week, until, 
setting at the same time with the sun, she bids 
farewell to the evening sky. You may look out 
to see her adorning it with her beauty ; you will 
look in vain. But she is not lost. 



THE PLANETS — VENUS AND MERCURY. 43 

11. In a few days she will appear in the eastern 
sky, just before sunrise. She is now called the 
Morning Star, The poets sometimes call her 
Lucifer, which means Light-bearer, because she 
brings in the dawn. Thus the prophet Isaiah, 
who was also a poet, addressing the King of 
Babylon, whom he likens to the Morning Star, 
says: 

" How art thou fallen from heaven, O Lucifer, Son of the Morn- 
ing !" 

She will be morning star just as long as she 
was evening star ; moving in the eastern sky as 
she then did in the western. 

12. Thus this wonderful planet seems to move 
back and forth, like the pendulum of a clock ; 
and changing from one side of the heavens to the 
other, she divides her time equally between the 
morning and the evening. But to the midnight 
sky she is a stranger. She is never seen at mid- 
night.* 

The only star whose motions are like hers is 
the planet Mercury. This planet can be seen 
only a few days, twice in the year. 



* Venus is never above the horizon more than three hours after 
sunset, nor does she ever rise more than three hours before sunrise. 



44 ASTRONOMY. 

13. The reasons why the motions of Venus 
and Mercury appear, to us on the earth, so differ- 
ent from the motions of the other planets, is 
because their orbits around the sun are nearer to 
him than the orbits of the earth and of the other 
planets. — See the picture of the Solar System, 
page 131. 

14. Hence, Mercury and Venus are called 
Inferior Planets, and the other planets are called 
Superior Planets. Inferior, you know, means 
below, and superior means above. 

Imagine yourselves to be standing on the earth, 
as represented in the picture of the solar system, 
page 131, and you will see the orbits of Mer- 
cury and Venus below you, and the orbits of all 
the other planets above you. Observe each orbit 
attentively, and you will never forget the distinc- 
tion between inferior and superior planets. 

15. As the orbits of the inferior planets, Mer- 
cury and Venus, lie between the orbit of the earth 
and the sun, these planets, in their revolution 
around the sun, sometimes come between him 
and the earth. As they are dark bodies, — when 
they do so, they will prevent the light between 
them and the sun from coming to us, and will 
appear as a round dark spot passing over the 



THE PLANETS — VENUS AND MERCURY. 45 

face of the sun. This is called a Transit. The 
word transit means a passing over. 

There have been many transits of Mercury and 
Venus, and there will be many more. The last 
transit of Venus occurred December 6, 1882, 
about two years ago. The next will occur in the 
year 2004, about one hundred and twenty years 
hence. 

Mercury goes around the sun oftener than 
Venus, and comes between him and the earth 
oftener. Hence it will have more frequent tran- 
sits. The next transits of Mercury will occur in 
May and November in the year 1891, about six 
years from now. 

When the last transit of Venus occurred, the 
whole astronomical world came out to watch for 
it. 

Many eminent astronomers, sent by their gov- 
ernments, at the expense of the nation, went to 
different parts of the four quarters of the earth, 
in order to observe this transit. A body of 
distinguished German astronomers came to the 
United States, and observed it, in Hartford, 
Connecticut. 



4 6 



ASTRONOMY. 



QUESTIONS. 



1. How many kinds of stars are 

there ? 

2. How do most of the stars ap- 

pear to move across the 
heavens? 
What are such stars called ? 

3. What stars are called planets? 
What does the word planet 

mean ? 

4. Which is the brightestand most 

most beautiful of all the 
stars ? 
What star appears first after 
sunset? 

5. Describe the light of Venus? 

6. How many stars have motions 

like Venus ? 

7. When is Venus called the 

Evening Star? 
How many months is she 

evening star at a time ? 
Where does she appear when 

she first becomes evening 

star? 
Which way does she seem to 

move every night? 
Do you know this to be a real 

motion ? 

8. Look at the picture on page 

41, and describe the other 
motion of Venus. 

9. Show me where she is, when 

she first appears as evening 

star. 
Show me which way she seems 

to move from week to week. 
Show me where she seems 

stationary. 



13. 



14. 



15. 



When Venus begins to move 
again, which way does she 
go? 

When Venus disappears from 
the evening sky, how long 
before she can be seen again? 

Where does she then appear ? 

What is she now called? 

How long will she continue 
to be morning star? 

How does she now appear to 
move? 

To what is this motion like? 

To what part of the sky is she 
a perfect stranger ? 

What planet's motions are like 
those of Venus ? 

How long a time, and how 
often, can Mercury be seen ? 

Why do the motions of Mer- 
cury and Venus appear to 
us so different from the 
motions of the other plan- 
ets ? 

Why are Mercury and Venus 
called inferior planets ? 

Why are the other planets 
called superior planets? 

Which alone of all the planets 
may come between the 
earth and the sun ? 

Why is this? 

Which of the planets can 
never come between the 
earth and the sun ? 

Why not? 

When Mercury and Venus 
come between the earth and 



THE PLANETS — JUPITER, ETC. 



47 



the sun, how do they ap- 
pear? 

What is this appearance 
called ? 

What does the word transit 
mean ? 

Have there been many tran- 
sits of Mercury and Venus ? 

Will there be many more? 

When was the last transit of 
Venus ? 

When will the next occur ? 



What planet has more frequent 
transits than Venus? 

Why has Mercury more tran- 
sits than Venus? 

When will the next transits of 
Mercury occur ? 

Can astronomers foretell 
when transits will happen ? 

Can Jupiter and the other 
superior planets ever have 
transits ? 

Why not? 



LESSON TENTH. 

THE PLANETS— JUPITER, AND THE OTHER SUPERIOR 
PLANETS. 

i. Jupiter appears almost as large and bright as 
Venus, but of a different color. Venus, you re- 
member, has a silvery whiteness like the moon. 
Jupiter, more like the sun, is of a golden hue. 

2. You will wish to know where to look, to 
see Jupiter. You must not look to the north or 
to the south. He is always somewhere in that 
part of the sky through which the sun and moon 
appear to move. The paths of all the planets lie 
near together, and near the path of the sun and 
moon. 

3. Jupiter, like Venus, has two motions. One 



48 ASTRONOMY. 

of them may be perceived every evening. This 
is called his daily motion, and is always from 
east to west. The other motion is back and 
forth from east to west, and from west to east. 

4. We never see Venus anywhere but in the 
eastern or western sky. She seems to move back 
and forth there between two limits. It is not so 
with Jupiter. Like Venus he appears to move 
back and forth in the sky, but not always in the 
same places. We see him not only in the east 
and west, but also overhead. 

5. There are four planets whose motions are 
like Jupiter's. Their names are Mars, Saturn, 
Hcrschel or Uranus, and Neptune. Only two of 
them can be often seen without a telescope. 
These two are Mars and Saturn. Mars appears 
of a fiery red color. Saturn is a large yellow star. 

The Asteroids, also lying between Mars and 
Jupiter, are Superior Planets, and have the same 
apparent motion as Jupiter and the others. 

6. Saturn is distinguished from all the other 
planets by a ring of light reflected from the sun, 
like the light of our moon. This ring encircles 
him midway between his North pole and his 
South pole, as represented in the picture, page 53. 
Eight moons are not enough ; so there is added 
the light of this glorious ring. 



THE PLANETS — JUPITER, ETC. 



49 



7. No naked eye of man has ever seen it. It 
was discovered by the use of the telescope, and 
can be seen only through the telescope. 

8. It appears to be divided into two rings, by 
a dark, narrow strip, as seen in the picture. 

Recent observations disclose the existence of a 
third ring, of a dusky hue, lying within the other 
two, and nearer to the body of the planet. 

9. Although astronomers speak of three rings, 
there seems to be, in fact, but one, since they all 
revolve around the planet in exactly the same 
period, as one substance. 

10. The matter of the ring is independent of 
the matter of the planet, and separate from it, 
since the planet revolves upon its axis in about 
ten and a quarter hours, while the ring requires 
a little longer time for its revolution, that is, 
about ten and a half hours. 



QUESTIONS 



1. How large and bright does 

Jupiter appear ? 
What is his color ? 

2. Where must you look to see 

Jupiter? 
Where are the paths of all the 
planets ? 

3. How many motions has Jupi- 

ter ? 
What is the motion, which can 



be perceived every evening, 
called ? 

Which way is this motion ? 

Which way is the other mo- 
tion of Jupiter? 

4. Where is Venus always seen ? 
Where may Jupiter be seen ? 

5. How many planets are there 

whose motions are like. 
Jupiter's ? 



5o 



ASTRONOMY. 



What are their names ? 

How many of them can be 

seen without a telescope ? 
What are their names ? 
What is their appearance ? 
What other superior planets lie 

between Mars and Jupiter ? 
What distinguishes Saturn 

from all the other planets ? 
How does this ring encircle 

him? 
Is this ring visible to the 

naked eye ? 
How was it discovered ? 
How can it be seen ? 



How does it appear to be 
divided ? 

What is the position and 
color of the third ring re- 
cently discovered ? 

How many rings are there in 
fact ? 

How does it appear that the 
three rings are, in fact, one? 

Is the matter of the ring sepa- 
rate from the matter of the 
planet and independent of 
it, or is it a part of the same 
matter ? 

What proves it to be separate 
and independent? 



LESSON ELEVENTH. 



THE ASTEROIDS. 



i. Between the orbits of Mars and Jupiter, 
there are two hundred and forty, or more, very 
small planets, called Asteroids. Asteroid means 
a small star. 

2. They are all invisible to the naked eye, ex- 
cept Vesta, which, though rarely, may be some- 
times seen without a telescope, and have been 
discovered by the use of the telescope. No one 
of them had been discovered before the year 



THE ASTEROIDS. 5 1 

1801. Between that year and 1807, f° ur °f 
them had been discovered. 

3. The names of these four are Juno, Vesta, 
Ceres, Pallas. The others have been discovered 
since, from time to time, by different astrono- 
mers, and named. 

4. The distance between the orbits of Mars 
and Jupiter was so great, that astronomers 
thought there must be planets between these two 
orbits. Hence they worked diligently, and dis- 
covered them. 

Look at the picture of the Solar System, page 
131, and imagine two hundred and forty orbits, 
lying between the orbit of Mars and the orbit 
of Jupiter, and two hundred and forty asteroids, 
revolving, each in its own orbit, about the sun. 

5. The Asteroids are extremely small. The 
largest of them is only three hundred miles in 
diameter. Compare this with the diameter of 
the earth, which is eight thousand miles, and you 
will see how small it is. The others are much 
smaller. Indeed, they are so small that some 
astronomers think they are parts of a large 
planet, now broken in pieces. Sir William Her- 
schel calls this idea a harmless dream. 



52 



ASTRONOMY. 



QUESTIONS. 



1. What are asteroids ? 

How many asteroids have been 

discovered ? 
Where are they situated ? 

2. Are they visible to the naked 

eye ? 

How were they discovered ? 

How many of them were dis- 
covered between the years 
1801 and 1807 ? 

When were the others dis- 
covered ? 

3. What are the names of these 

four? 



Have the asteroids all been 

named ? 
By whom ? 

4. Why did astronomers think 

there must be planets be- 
tween Mars and Jupiter ? 

5. What is the magnitude of these 

planets ? 
What idea, as to their origin, 

do some astronomers derive 

from their smallness ? 
What does Sir William Her- 

schel call this idea ? 



LESSON TWELFTH. 

THE PLANETS ARE WORLDS. 

i. I think the planets are great worlds, with 
skies and sun, and moons, and stars, like the 
Earth on which we live. I will tell you why I 
think so. 

2. First ; they are dark bodies like the Earth. 
— They look bright to us for the same reason 
that the moon looks bright* The light from 



* The teacher should here recur to the explanation given on page 
26, and see that the pupil understands it. 



THE PLANETS ARE WORLDS. 53 

some luminous body falls on them, and is re- 
flected to us. Some of them have phases like 
our moon. The phases are not visible to the 
naked eye, but with a telescope they may be dis- 
tinctly seen. Venus, for example, appears new, 
half, gibbous, and full, just like the moon. 

If Venus shone with her own light, this would 
not be possible. She would always appear to 
us a round, full orb, like the sun. 

3. Second ; I think the planets are like the 
Earth, because some of them have moons. — Mars 
has two moons, Jupiter four, Saturn eight, and 
Herschel or Uranus six, Neptune one. If we 
look at these planets with a telescope, we can 
see the moons. The planets must be worlds like 
our earth, or they would have no need of moons. 




54 ASTRONOMY. 

4. Third ; Some of the planets, when seen 
through a telescope, look round like a ball, which 
you remember is the shape of the Earth. I saw 
Saturn a few days ago through a telescope. He 
looked like a ball of light about as big as a walnut. 
He seemed to be swimming in a blue sea, sur- 
rounded by a wide ring or border of light, with a 
narrow strip of dark near the middle. I never 
saw anything more beautiful. 

5. Fourth; The planets are like the Earth, 
because they turn round like a ball. — We cannot 
see the motion. But with a telescope we can 
see dark spots on the planets. If we watch any 
one of these spots, we shall soon perceive that it 
has moved. By and by it goes out of sight, and 
after a while appears again where we first saw it. 

Make the head of a pin black in the candle- 
smoke, stick it in the side of an apple, and then 
turn the apple round The pin-head will move, 
go out of sight, and appear again, just like the 
spots on the planets. In this way we learn that 
the planets revolve in a certain number of hours, 
like the Earth. I believe they do so, to make 
their day and night. They must be worlds, or 
they would have no need of day and night. 

6. If the planets are great worlds, like the 
Earth, you will wonder that they should look like 
little bright spots in the sky. It is because they 



THE PLANETS ARE WORLDS. 55 

are very far off. When the people on the planets 
look up at their sky, they see the Earth appear- 
ing like a bright star, just as the planets appear 
to us. Astronomers call the Earth a planet, 
because it is a dark, round body, has a moon, 
and revolves, just like the planets which we see in 
the heavens. 

7. The sky around some of the planets must 
be even more splendid and beautiful than our sky. 
Nothing can appear more magnificent than the 
evening sky of Saturn. 

To a spectator on the planet, the ring looks 
like a broad arch of light, with a narrow strip of 
dark, extending quite across the heavens. Moons 
appear, shining together, in every variety of phase, 
— new, half, gibbous, full, and old ; some rising, 
some on the meridian, some setting, and, it may 
be, some in eclipse. Imagine the scene ! 

With what adoring wonder at the power and 
wisdom of the Creator must the inhabitants of 
Saturn, if such there be, standing under their 
open sky, gaze upon a sight so glorious ! 

QUESTIONS. 



1. What are the planets? 

2. Are the planets light bodies, 

or dark bodies ? 
Why do they look bright to us ? 



What have they, like our moon? 
How can we see the phases ? 
3. What planets have moons, like 
the earth ? 



56 



ASTRONOMY. 



How many moons has Neptune? 

How many has Jupiter? 

How many has Saturn ? 

How many has Herschel? 

How many has Mars? 

How does the planets having 
moons show that they are 
worlds ? 

What is the shape of the earth ? 

What is the shape of the plan- 
ets ? 

How does Saturn look when 
seen through a telescope ? 

How does the earth turn round? 

Do the planets turn round in 
the same manner ? 



Can you see their motion ? 
How, then, do you know that 

they turn round ? 
Why do the planets turn round ? 
If the planets are great worlds, 

why do they look like little 

bright spots in the sky ? 
How does the earth appear to 

the people on the planets ? 
Why do astronomers call the 

earth a planet ? 
Describe Saturn's evening sky, 

as it appears to a spectator 

on the planet ? 



LESSON THIRTEENTH. 



THE FIXED STARS. 



i. Number. — As night begins to approach, a 
single star appears. Then others become visible ; 
and when it becomes quite dark, the whole sky 
seems to twinkle. 

2. The stars appear very numerous. We think 
we see a great many thousands. But we are 
deceived. To the naked eye, only about two 
thousand stars are visible, at any one place, at 
any one time. 



THE FIXED STARS. 57 

3. The stars have been counted. There are 
about seven thousand stars visible to the naked 
eye. But they are not all visible to us at the same 
time. Some of them are in the skv on the other 
side of the earth, and we cannot see them until 
they appear in our sky. Some of them are in 
the sky around the South pole, and we never see 
them, where we are. 

The telescope reveals to us that the stars are a 
great many millions in number, perhaps so many 
that God alone can count them. 

Look at the picture opposite to page i. The 
children, represented there as standing on the 
earth, can see the stars above them, and those 
around the North pole, but they cannot see those 
on the other side of the earth, nor those around 
the South pole, because the earth is between 
them and those stars.* 

4, Magnitude. — The stars seem to be of dif- 
ferent magnitudes. Those which appear largest 
are called stars of the first magnitude; the next 
largest, stars of the second magnitude, and so on 
to the smallest stars visible to the naked eye, 
which are of the sixth magnitude. Thus there 



* The teacher should take particular care to see that the pupil 
understands this illustration. 



58 ASTRONOMY. 

are six classes of stars, according to their apparent 
size, as represented in this picture. 



You must not suppose that the apparent magni- 
tudes of the fixed stars represent their real magni- 
tudes. For example, Sirins, the brightest of 
them, may be smaller than the faintest of the 
Pleiades. It may be, that he appears so large 
and bright because he is nearer to us, and it may 
be partly because he is really larger, and partly 
because he is really nearer. 

5. Distance. — Astronomers have been able to 
determine the distance of the sun, moon, and 
planets, from the earth, and from each other, but 
not the distance of the fixed stars. 

We know that, remote as they are, some of 
them are nearer to us than others. But their 
actual distance is so vast, that no human being 
has as yet been able even to compute it. As you 
have learned on page 30, the sun, moon, and 
planets have disks, or faces, which can be mea- 
sured. But the fixed stars have no disk capable 
of measurement. They are so distant that they 
appear only as brilliant points. 

6. Motion. — The stars have two apparent mo- 



THE FIXED STARS. 59 

tions, a daily motion, and an annual or yearly 
motion. They appear to move every evening, 
in exact order, towards the west. Watch any 
stars which you see in the east, just after sunset, 
and about midnight, you will see them together 
overhead, and in the morning, going down to- 
gether towards the western horizon. This is 
called their diurnal or daily motion. The revo- 
lution of the Earth, every day towards the east, 
would make the stars, like the sun, appear to 
move towards the west. 

7. The annual motion of the stars is also to- 
wards the west. You cannot perceive this motion 
by watching them a single evening. But if you 
observe where any star is this evening, and after 
several evenings, look for it again, at the same 
hour, you will see it farther west. Stars which 
appear in the east to-night at dark, three months 
hence, at the same hour, will be overhead, and 
six months hence, in the west. 

While the stars seem to move through the sky 
every night, it seems as though the sky itself was 
slowly turning from east to west the whole year, 
carrying the stars along with it. 

The motion of the Earth in her orbit, around 
the sun, would give the stars this apparent mo- 
tion. 



6o 



ASTRONOMY. 



QUESTIONS. 



i. Are the stars all visible at once 
when night begins to ap- 
proach ? 

2. How many stars do there ap- 

pear to be? 
How many can we really see 
at once ? 

3. How many stars are there in 

all, visible to the naked eye ? 

How do you know this? 

Are they all visible to us at the 
same time? 

Where are those which are not 
visible? 

What stars can never be seen, 
where we are ? 

Look at the picture opposite 
page 1, point to the group of 
children standing there on 
the earth, and show me what 
stars they can see, and what 
stars they cannot see. 

4. How many classes of stars are 

there, according to their ap- 
parent magnitude ? 

What are the stars which ap- 
pear largest called ? 

What are the next largest 
called ? 

What are the smallest stars vis- 
ible to the naked eye called ? 

Do their apparent magnitudes 
represent their actual magni- 
tudes ? 

Why may the brightest star, 
Siritis, for example, be actu- 
ally smaller than the faintest 
of the Pleiades ? 

5. Have astronomers been able 

to determine the distances 



of the fixed stars from the 
earth ? 

Why not? 

Have they ascertained that 
some of them are nearer to 
us than others ? 

Have the fixed stars any disk ? 

Why not? 

How do they appear to us? 

Why is this ? 

Why do they not appear like 
the sun, moon, and planets? 

How many apparent motions 
have the stars ? 

What are they called ? 

How do the stars appear to 
move every evening? 

Where will stars, which appear 
in the east just after sunset, 
be seen at midnight ? 

Where will they be seen in the 
morning ? 

What is this motion called? 

What would make the stars ap- 
pear to move in this way, 
although perfectly still ? 

Which way is the annual mo- 
tion of the stars ? 

Can it be perceived by watch- 
ing them a single evening? 

How may you perceive it? 

Where will stars, which appear 
in the east, at dark to-night, 
be seen at the same hour, 
three months hence ? 

Where will they be six months 
hence ? 

What would give the stars this 
apparent annual motion, al- 
though perfectly still ? 



DIVISIONS OF THE HEAVENS. 6l 

LESSON FOURTEENTH. 

DIVISIONS OF THE HEAVENS. 

1. You have learned from Geography that the 
Earth is considered as divided into Northern and 
Southern, Eastern and Western Hemispheres. 
So are the Heavens. The Northern Hemisphere 
of the Heavens is over the Northern Hemisphere 
of the Earth, the Southern over the Southern, 
and so on with the others. 

2. The Meridian of the Earth is a line, 
imagined to be drawn around it, north and south, 
dividing it into two hemispheres, called the East- 
ern and Western Hemispheres of the Earth. 
The Meridian of the Heavens is a line, im- 
agined to be drawn on them, directly over the 
Meridian of the Earth, dividing them into the 
Eastern and Western Hemispheres of the Hea- 
vens. 

3. The Equator of the Earth is a line, 
imagined to be drawn around it, east and west, 
dividing it into Northern and Southern Hemi- 
spheres. The Equator of the Heavens is a 
line, imagined to be drawn in like manner around 



62 ASTRONOMY. 

the heavens, and exactly over the Equator of the 
Earth. It is also called the Equinoctial. 

4. The Ecliptic is the path in which the sun 
appears to move, in passing across the heavens. 

5. The Zodiac is a broad strip of the heavens, 
lying half on one side, and half on the other side, 
of the ecliptic or sun's path. The Moon, Jupiter, 
Venus, and almost all the planets always move 
through this part of the sky. Their paths are 
said to lie within the Zodiac. 

6. The Milky Way is another broad strip, 
extending like a great white band across the hea- 
vens, northeast and southwest. It is called the 
Milky Way, because it is white like milk. You 
can see it every night when the sky is clear. 

7. Constellations. — At first sight the stars 
seem to be scattered all over the sky, without any 
arrangement. But when you observe them more 
attentively, you see that they are arranged in clus- 
ters or groups. These clusters or groups are 
called Constellations. The word constellation 
means several stars lying close together. 

8. The constellations have all been counted 
and named. They are ninety-one in number. 
Thirty -four of them are in the Northern Hemi- 
sphere, north of the Zodiac, twelve of them are in 
the Zodiac, and forty-five of them in the South- 



DIVISIONS OF THE HEAVENS. 



63 



ern Hemisphere, south of the Zodiac. The stars 
in the Zodiac, north of the Equinoctial, are in the 
Northern Hemisphere. The stars in the Zodiac, 
south of the Equinoctial, are in the Southern 
Hemisphere. 

9. Thus you perceive that Astronomy resem- 
bles Geography. The heavens are supposed to 
be divided into hemispheres, constellations, etc., 
that we may be able to describe the situation of 
stars in the heavens, just as we describe the situ- 
ation of places on the earth. Thus we say, Arc- 
turns is in the Northern Hemisphere, in the con- 
stellation Bootes, just as we say, Quebec is in the 
Northern Hemisphere, in the province of Lower 
Canada. 

QUESTIONS. 



1. Into what hemispheres are the 

heavens imagined to be 
divided? 

Where is the northern hemi- 
sphere of the heavens ? 

Where is the southern ? 

Where is the eastern ? 

Where is the western ? 

2. What is the meridian of the 

earth ? 

How does it divide the earth ? 

What is the meridian of the 
heavens ? 

How does it divide the hea- 
vens? 

3. What is the equator of the 

earth ? 



What is the equator of the hea- 
vens? 

By what other name is it some- 
times called? 

4. What is the ecliptic? 

5. What is the zodiac ? 

What heavenly bodies are 
always within the zodiac ? 

6. What is the milky way ? 

Why is it called the milky way ? 

7. How do the stars at first sight 

appear to be scattered over 
the sky ? 
How do they appear to be ar- 
ranged when observed atten- 
tively ? 



6 4 



ASTRONOMY. 



What are the clusters or groups 
of stars called ? 

What does the word constella- 
tion mean ? 

How many constellations are 
there ? 

How many of these are in the 
zodiac ? 

How many in the northern 
hemisphere, north of the 
zodiac ? 



How many in the southern, 
south of it ? 

For what purpose are the hea- 
vens supposed to be divided 
into hemispheres, constella- 
tions, etc.? 

Describe, for example, the situ- 
ation of the star Arc turns. 

Describe the situation of 
Quebec. 



LESSON FIFTEENTH. 



STARS OF THE FIRST MAGNITUDE. 

i. There are twenty-two stars of the First 
Magnitude. Eleven of them are in the Northern 
hemisphere, that is, north of the equinoctial 
Eleven of them are in the Southern hemisphere, 
that is, south of the equinoctial. For the mean- 
ing of the word equinoctial, see page 62. 

2. Some of these stars are a little smaller than 
the others, and, although called stars of the first 
magnitude, may be, in fact, between the first and 
second magnitudes. 

3. The following are the names of all the stars 
of the first magnitude, in the order of their dis- 
tances from the equinoctial, and the names of the 
constellations in which they are situated : 



STARS OF THE FIRST MAGNITUDE. 65 

In the Northern Hemisphere : Procyon, in the 
Lesser Dog ; Betelgeux, in Orion ; Altazr, in the 
Eagle ; Regulus, in the Lion ; Aldebaran, in the 
Bull; Arcturus/xw Bootes; Alpherat, in Andro- 
meda ; Vega, in the Lyre ; Deneb, in the Swan ; 
Cappella, in Auriga ; and Dubhe, in the Greater 
Bear. 

Thus you will observe that Procyon is farthest 
south, and Dnbhe farthest north, of all the stars, 
of the first magnitude, in the Northern Hemi- 
sphere. 

4. In the Southern Hemisphere, nearest the 
equinoctial, are : first Rigel, in Orion ; then Spica 
VtrginzSy in the Virgin ; Sirius, in the Greater 
Dog; AntareSy'm the Scorpion; Fomalhaut, in 
the Southern Fish ; Canopus, in the Ship Argo ; 
Achernar, in Eridanus ; Agena and Bungula, in 
the Centaur; Alpha Cruris, in the Southern 
Cross ; and Maia Placida, in the Ship Argo. 

Thus you will observe, that of all the stars, of 
the first magnitude, in the Southern Hemisphere, 
Rigel, in Orion, lies nearest the equinoctial, that 
is, farthest north, and Maia Placida farthest from 
the equinoctial, that is, farthest south. 

5. In order to have a true idea of the places of 
the stars in the heavens, you must imagine to 
yourselves the place of the equinoctial, — midway 



66 



ASTRONOMY. 



between the North Pole and the South Pole. If 
a star is in the Northern Hemisphere, but not far 
north, look for it near the equinoctial. If it be 
far north, look for it far north of the equinoctial. 
If a star be in the Southern Hemisphere, but 
not far south, look for it on the southern side of 
the equinoctial, but not far from it. If it be far 
south, look farther south. 



QUESTIONS. 



1. How many stars of the first 

magnitude are there ? 
How many of them are in the 

northern hemisphere ? 
How many of them are in the 

southern hemisphere? 

2. Are these stars all exactly of the 

same apparent magnitude? 

3. Name the stars of the first mag- 

nitude, in the northern hemi- 
sphere, in the order of their 
distances from the equinoc- 
tial, and the constellations in 
which they are situated. 
Which is the farthest north, 
and which the farthest south, 
of all the stars of the first 
magnitude, in the northern 
hemisphere ? 



Name the stars of the first 
magnitude in the southern 
hemisphere, in the order of 
their distances from the equi- 
noctial, and the constella- 
tions in which they are situ- 
ated. 

Which is the farthest north, 
and which the farthest south, 
of all the stars of the first 
magnitude in the southern 
hemisphere? 

In what way can you form a 
true idea of the places of the 
stars in the heavens, and find 
them ? 



THE POLE STAR — THE GREAT DIPPER. 67 

LESSON SIXTEENTH. 

THE POLE STAR— THE GREAT DIPPER. 

i. There is one star which appears to be 
always in the same place. It is almost exactly in 
the north, and is called the Pole Star. Some 
ancient astronomers called it Alrucaba. While 
all the other stars seem to be in ceaseless motion, 
there it remains, from evening to evening, and 
from year to year, always visible, unless hidden 
by clouds. 

2. You will wish to find this wonderful star. 
You must first find the Great Dipper. There 
are seven stars, in the northern sky, which make 
a figure shaped like a great dipper. Their names 
are Ditbhe, Merak, Megres, Phad, Alioth, Mzzar, 
and Benetnasck. Look at the situation of each 
of them, as represented in the Great Bear, on 
page 72. 

3. When you have found the Dipper, you can 
easily find the Pole Star. There are two stars in 
the Dipper, called Pointers, because they always 
point to a solitary bright star about half-way be- 
tween the northern horizon and the zenith. This 
is the pole star. See the Pointers, on the picture, 



ASTRONOMY. 




The Dipper going round the Pole Star. 



THE POLE STAR — THE GREAT DIPPER. 69 

always pointing to the pole star. Go out when 
it is a clear evening and find them in the sky ; 
then look where they point, and you will see the 
pole star. The names of the Pointers are Dubhe 
and Merak. These stars are in the eastern cor- 
ners of the Dipper. The uppermost star is Dubhe ; 
the lower one, Merak. 

4. But you will not always find the Dipper in 
the same place ; it is continually moving. It has 
two motions — a daily motion and a yearly mo- 
tion. It seems to revolve round the pole star 
once every twenty-four hours. If it appears in 
the northeast early in the evening, at midnight it 
will be right over the pole star, and in the morn- 
ing will be seen in the northwest. It takes six 
hours to go one quarter of the way round, twelve 
hours to go one half, and so on. In this way it 
shows the time of night. 

5. While the Dipper revolves every night, it 
also seems to be turning slowly round throughout 
the whole year. Thus, in the fall, it appears, at 
dark, in the north, below the pole star, in winter, 
in the northeast, in spring, above the pole, and in 
summer, in the northwest. — See it in these four 

positions on the picture* — In this way it shows 

* The student must always remember that the motion of the con- 
stellations and of the stars is apparent only. The real motion is the 
motion of the Earth. 



7o 



ASTRONOMY. 



the time of year. Will you not wish to observe 
this great clock which God has made, and sus- 
pended in the sky ? 

6. The pole star has been observed more than 
any other star in the sky. It is not so bright and 
beautiful as many others, but it has been very 
useful to mankind. The sailor on the wide 
ocean, the Indian in the pathless forest, and the 
caravan on the sandy desert, all watch this star, 
and by it direct their course. There it always 
stands in the heavens, a sure and never-sleeping 
guide. 

QUESTIONS. 



1. How many stars appear to be 

always in the same place ? 
Where is this star? 
What is it called ? 

2. What must you first find in 

order to find the pole star? 
How many stars make the 

Great Dipper? 
What are their names? 
In what part of the sky is it ? 

3. When you have found the Dip- 

per, how can ) r ou find the 
pole star? 
What are the names of the 
Pointers? 

4. Can you always find the Dipper 

in the same place ? 
Why not? 
How many and what motions 

has it ? 
What does it seem to revolve 

round ? 
How often ? 



If it appears in the northeast 

early in the evening, where 

will it be at midnight ? 
Where in the morning? 
How long does it take to go 

one quarter of the way 

round ? 
How long to go one half? 
What does it in this way show ? 
How does the Dipper appear 

to move during the whole 

year? 
Where is it seen, at dark, in the 

fall? 
Where in winter? 
Where in spring? 
Where in summer? 
Why has the pole star been 

observed more than any 

other star in the sky ? 
Who watch this star in order 

to direct their course ? 



CONSTELLATIONS ALWAYS VISIBLE. 7 1 

LESSON SEVENTEENTH. 

CONSTELLATIONS ALWAYS VISIBLE. 

i. I shall now describe some of the most re- 
markable Constellations. I shall tell you where 
they are situated, how they look, and when they 
may be seen, that you may be able to find them 
in the sky, or when you see them, may know 
their names. 

2. The constellations around the pole star are 
visible to us every night throughout the year, un- 
less hidden by clouds. We never have the earth 
between us and them. The little group on the 
picture, opposite to page i, stand on the earth, 
near where we are. Look at them, and you will 
perceive that they can see the sky all around the 
pole star. 

3. The Great Bear. — On the following page, 
is a picture of a constellation, called the Great 
Bear; it is situated in the northern sky, and re- 
volves around the pole star. 

Find the Great Dipper, and then you can easily 
find the Great Bear. The Great Dipper is in 
this constellation, and contains its brightest stars. 



J2 



ASTRONOMY. 



It will seem strange to you that a cluster of stars 
should be called Great Bear. I cannot see that 
it looks like a bear, but it has been called the 
Great Bear thousands of years, and is every- 
where known by this name. Almost all the 
constellations are called by the names of men, 




women, animals, snakes, birds, or fishes. Some 
few of them look a little like the objects whose 
names they have. 

4. Arcturus. — At some distance south of the 
stars in the tail of the Bear, or which is the same 
thing, in the handle of the Dipper, is a very large, 



CONSTELLATIONS ALWAYS VISIBLE. 73 

reddish star, called Arcturus. It is the largest 
and brightest star ever seen in the northern sky. 
On account of its superior size and brightness, 
the writer of the Book of Job seems to have 
fancied it the father or patriarch of the whole 
family of stars in this region. He speaks of 
Arcturus and his sons. It was once considered 



V Pole Star 




as situated in the Bear's tail. The word Arc- 
turus means, In the Bears tail. But his tail 
must be very long to reach that star. 

The Little Bear. — Here is another bear; it 
is called the Little Bear. 

The Little Bear is another of those constel- 
lations which revolve around the pole star. It is 
nearer the pole star than the Great Bear. The 



74 ASTRONOMY. 

pole star is in the end of its tail. It does not 
look like a bear, but there are seven stars in it 
which make a figure that really looks like a dip- 
per. This figure is called the Little Dipper. 
The end of the handle is the pole star, around 
which the Dipper revolves once a day and once 
a year, just like the Great Dipper. It does not 
appear so plain as the Great Dipper, and you 
must not be disappointed, if you cannot find it, 
until some one has first shown it to you. 

5. The polar regions of the earth are the coun- 
try of bears; here they roam over the trackless 
snows and the fields of ice, without fear of man. 
Perhaps this is the reason why two constella- 
tions, in the polar regions of the Heavens, have 
been called bears. 

6. Cassiopeia. — Find the Great Dipper, then 
look in the sky on the opposite side of the pole 
star, at about an equal distance from it, and you 
will see six beautiful though not very large stars, 
making a figure shaped like a chair turned over. 
Four of them make the bottom part, and two 
the back. These are the brightest stars of a con- 
stellation called Cassiopeia. Observe the picture 
on page 75. Schedir and Caph are in the bot- 
tom of the chair. Ruchbah is the middle star in 
the back of the chair. 



CONSTELLATIONS ALWAYS VISIBLE. 



75 



7. Cassiopeia is the name of a queen who once 
lived in Ethiopia. She was very beautiful, and 
greatly admired. After she died her name was 
given to this constellation. Perhaps it was really 
believed that she had gone up to heaven, to live 




Cassiopeia. 



in these fair stars. Or perhaps it was that when 
men should look up in the sky and behold them, 
they might remember Cassiopeia and her beauty. 
In this picture Cassiopeia is represented as a 
queen sitting in her chair, holding her robe in one 



76 



ASTRONOMY. 



hand and a palm-leaf in the other. If you expect 
to see anything in the sky, looking like this pic- 
ture, you will be disappointed. But you can see 
the chair-shaped figure. 

8. Cassiopeia seems to revolve around the pole 
star, just like the Dippers and the Bears. All 
the stars in this part of the sky appear to revolve 
round it in the same manner. 

9. In eastern countries, men, as they lay under 
the open sky, could observe this motion of the 
stars all night. They seem to have regarded it 
with the greatest admiration. It is mentioned in 
the Bible as one of the most remarkable examples 
of divine skill. God says to Job, " Canst thou 
guide Arcturus and his sons?" How very small 
indeed the wisdom and power of man compared 
with His who guides this patriarch of stars, with 
his sons, in their wonderful motion round the* 
heavens ! 



QUESTIONS. 



2. 



What constellations are always 
visible ? 

Turn to the picture opposite 
page 1, and show me why 
we can always see these con- 
stellations. 
Where is the constellation, 
called the Great Bear, situ- 
ated? 

What does it revolve round ? 



How can you easily find this 

constellation? 
Does this constellation look 

like a bear ? 
How long has it been called 

so? 
Where is it known by this 

name? 
By what names are most of 

the constellations called ? 



SUMMER CONSTELLATIONS. 



77 



Do any of them resemble the 

objects whose names they 

bear? 
What is the name of the largest 

and brightest star in the 

northern sky ? 
Where is it situated ? 
Why was it fancied to be the 

patriarch of the stars in this 

region ? 
Where was it once considered 

as situated ? 
What does the word Arcturus 

mean ? 
What is the Little Bear? 
Which is nearest the pole star, 

the Great Bear, or the Little 

Bear? 
In what part of the Little Bear 

is the pole star ? 
Does this constellation look 

like a bear ? 
What figure is made by seven 

stars in this constellation ? 



What star is the end of the 

handle ? 
What does the Little Dipper 

revolve round ? 

6. How can you find the constel- 

lation Cassiopeia ? 

7. What was Cassiopeia the name 

of? 
Why was her name given to 

this constellation ? 
Look at the picture and show 

me the chair-shaped figure 

in this constellation ? 

8. What does Cassiopeia revolve 

round ? 
What stars appear to revolve 
in the same manner? 

9. How was this motion of the 

stars regarded in eastern 
countries? 

Where is it mentioned as a 
remarkable example of di- 
vine skill ? 

What does God say to Job 
about this motion ? 



LESSON EIGHTEENTH. 



SUMMER CONSTELLATIONS. 



i. Some of the constellations appear in our 
evening sky only in summer. In our winter 
evenings they are in the sky on the other side of 
the earth. People in Europe, Asia, and Africa, 



78 ASTRONOMY. 

see them, but they do not come into our sky 
until daytime, when we cannot see them. 

2. The summer constellations which contain 
the brightest stars are the Lyre, the Eagle, the 
Swci7t, and the Scorpion. 

3. The Lyre. — This constellation may be 
known from its principal star, Lyra, also called 
Vega. It shines with a remarkably bright, sil- 
very light. 

4. About the first of June, Lyra, or Vega, rises 




at sunset, in the northeast. You may see it 
every evening when it is clear, from this time 
until January. It appears higher and higher up 
at dark until October, when it is nearly overhead. 
Now it begins to descend farther and farther 
west, and at last in January it can be seen for a 
few days setting in the northwest, soon after the 
sun ; and finally it disappears to be seen no more 
in our evening sky, until June comes again. 



SUMMER CONSTELLATIONS. 79 

5. It is said that there lived, thousands of years 
ago, a musician, named Orpheus. He made such 
music with his lyre that the rivers stopped to 
hear him, the wild beasts stood still and listened, 
and even the trees on the mountains came danc- 
ing down to meet him. When he died, the 
gods placed his lyre in the sky, and it became 
the constellation Lyra. 

6. Arided. — Somewhat northeast of Lyra, 
and at considerable distance from it, is another 
bright, w T hite star, Its name is Arided; it is in 
the constellation called the Swan. 

j. Altair. — Southeast of Lyra, and farther 
from it than Arided, is another bright, white star, 
named Altair; it is in the constellation called 
The Eagle. 

If lines, could be drawn in the sky, joining the 
three stars, Lyra, Arided, and Altair, these lines 
would form a large triangle having a bright sil- 
very star in each corner. 

QUESTIONS. 



1. Some of the constellations ap- 

pear in our evening sky only 
in summer ; where are they 
in our winter evenings? 
In what countries can the peo- 
ple see them at that time? 

2. What are the summer constel- 



lations which contain the 
brightest stars? 

How may the Lyre be known ? 

What is the name of this star? 

What is its appearance? 

When does Lyra rise at sun- 
set? 



8o 



ASTRONOMY. 



Where does it rise? 

How long will it remain visible 

in our evening sky ? 
In what month is it nearly over- 
head at dark ? 
Which way does it begin to 

descend ? 
Where can it be seen a little 

after sunset, in the month of 

January ? 
Whose lyre is this constellation 

said to be ? 
Relate the story of Orpheus. 
Which way from Lyra is the 

star Arided situated ? 



What is its appearance? 
In what constellation is it? 
What bright star south-east of 

Lyra? 
Which is farthest from Lyra, 

Arided or Altair? 
In what constellation is Altair? 
If lines should be drawn in the 

sky joining Lyra, Arided, and 

Altair, what figure would 

they make ? 
What would the triangle have 

in each corner ? 



LESSON NINETEENTH. 



SUMMER CONSTELLATIONS— Continued. 

i. Virgo. — There is a constellation called 
Virgo, or the Virgin, situated in the Zodiac, or 
sun's path. It contains one bright star, called 
Spica Virginis. Spica means an Ear of Grain, 
Spica Virginis means Virgin's Ear of Grain. 

2. This star first appears in our evening sky in 
the month of April, and continues to do so until 
some time in October, when it sets with the sun. 
It is situated southwest of Arcturus, which, when 
Spica first appears in the east, may be seen in the 
northeast, and higher up in the sky. Find Arc- 



SUMMER CONSTELLATIONS. 8 I 

turus, and then look some way southwest of it, 
and you will see Spica. 

3. In eastern countries young ladies used to go 
out in the fields after the reapers, and glean or 
gather the grain which they had left. The Bible 
relates a beautiful story of Ruth, who did so. 
Now it is said that in eastern countries this con- 
stellation used to be overhead with the sun at 
the time of harvest, and that for this reason it 
was represented as a virgin with an ear of grain 
in her hand. 

4. The Scorpion. — This is one of the twelve 
constellations of the Zodiac. It is situated some 
way east of Virgo. It appears in our evening 
sky about the first of June, and continues visible 
to us, but farther and farther west, until about 
the last of November. It really resembles a 
scorpion. 

5. You may easily know it from its largest 
star, called Antares, which is of a fiery red. This 
star is imagined to be in the heart of the scorpion. 
There is a long crooked line of stars forming the 
body and the tail, with stars branching off each 
side, making the claws and the legs. 



82 



ASTRONOMY. 




QUESTIONS. 



i. Where is the constellation 
Virgo ? 

What is the name of its bright- 
est star ? 

What does Spica mean ? 

What does Spica Virginis 
mean? 
2. In what month does this star 
first appear in our evening 
sky? 



In what month does it disap- 
pear from it ? 

Which way is it from Arcturus ? 

When Spica first appears in the 
east, where may Arcturus be 
seen ? 

Where may he be seen when 
it disappears in the west ? 

Why was this constellation 
called the Virgin ? 



WINTER CONSTELLATIONS. 



83 



Why was this star called Spica ? 
Where is the constellation 

called the Scorpion? 
In what month does it first 

appear in our evening sky ? 
Which way is it from Virgo ? 
How long does it continue 

visible to us ? 



Does it resemble a scorpion ? 
How may you easily know it ? 
In what part of the Scorpion is 

Antares ? 
What forms the body and tail 

of the Scorpion ? 
What form the claws and legs ? 



LESSON TWENTIETH. 



WINTER CONSTELLATIONS. 

i. The constellations which appear in our even- 
ing sky in winter are very splendid. Six stars 
of the first magnitude are seen all blazing at once, 
and in the same part of the heavens, and eight or 
nine stars of the second magnitude. When, be- 
sides all these, Jupiter, in his majesty, and Venus, 
in her beauty, appear at the same time, as they 
do if they happen then to be evening stars, the 
scene is brilliant indeed. 

2. The winter constellations containing the 
brightest stars are seven in number. Their names 
are : Orion, The Greater Dog, The Lesser Dog, 
The Bull, Auriga or The Wagoner, The Twins, 
and The Lion. The six first, whether they be in 
the east, overhead, or in the west, appear to- 
gether, as represented in the following map. 



8 4 



ASTRONOMY. 



\Af^\ AURIGA \ ^ EU 

;• THE TWINS ^ THE BULt ^ \ 

■--•• IjsP £~& A 

ORION \ -v^T 

Z , i -X/ 

GREATER '; w*r*£- y / 

DOG L * ^Ertitf 1 -..••••*•• 



mffl 



w 



\#J 



Y* 









Map of Winter Constellations. 



WINTER CONSTELLATIONS. 



85 



QUESTIONS ON THE MAP. 



What are the names of the con- 
stellations represented on the 
map ? 

How many stars of the first mag- 
nitude in Orion ? 

What are their names ? 

Which of them is farthest north ? 

Which farthest east? 

How many of the second magni- 
tude ? 

What very bright, large star 
southeast of Orion ? 

In what constellation is Sirius ? 

Which way is Procyon from 
Sirius ? 

Which way from Orion ? 

Of what magnitude is it ? 

In what constellation is it ? 

What large star northwest of 
Orion ? 

In what constellation is Aldeb- 
aran? 



What clusters of stars in this con- 
stellation ? 

How many stars form the Plei- 
ades? 

Which is farthest north — Aldeb- 
aran or the Pleiades ? 

Which farthest east ? 

What large star almost directly 
north of Orion ? 

Of what magnitude is Capella? 

Which way are the twins from 
Orion ? 

What are their names ? 

Of what magnitude are they ? 

Which way are the Twins from 
the Pleiades ? 

Which way from Procyon ? 

Mention the names of the six 
largest stars on the map, and 
the constellations in which each 
is situated ? 



LESSON TWENTY-FIRST. 

WINTER CONSTELLATIONS— Continued. 



1/ Orion. — Orion is the name of a famous 
hunter, celebrated in Grecian fables. It is said 
that he was a giant. Standing in the very midst 
of the sea, the waters reached only to his shoul- 
ders. Being stung in the foot by a scorpion, he 



86 



ASTRONOMY. 



died, and was placed in the heavens, where he is 

still imagined to have the appearance of a hunter. 

2. Several small stars are imagined to form a 




lion's head, which he is holding in one hand as a 
shield ; others form a club, which he is holding 
in the other hand. Some small stars in a row 
form his sword, which is girded on by a belt com- 



WINTER CONSTELLATIONS. 87 

posed of three stars in a row You perceive 
that he is holding up one foot. This is the foot 
which was stung. 

3. I need not tell you that you will see nothing 
in the Heavens resembling this picture. But you 
will see there a very remarkable constellation. 
Observe it once, and you will always know it. 
You will discover, as represented in the picture, 
four stars, two of them very bright, which you 
may easily imagine to make the corners of a long, 
square-like figure, with three bright stars, in a 
row, nearly in its midst. Look on the picture 
and learn the names of these four stars, so that 
you can point to them in the sky. 

4. Orion rises nearly in the east, passes the 
meridian south of us, and sets nearly in the west. 
It appears in our evening sky soon after sunset, 
early in December, and continues visible to us 
until June, when it may be seen setting a little 
after the sun. Job seems to have admired this 
constellation as one of the most magnificent of 
the Creators works. He says, "Who maketh 
Arcturus, Orion, Pleiades, and the Chambers of 
the South.'' 

5. Northw r est of Orion is a constellation of the 
Zodiac, called Taurus, or The Bull. You will 
know it from a fiery-red star, called Aldcbaran, 



88 



ASTRONOMY. 



which means The Torch, and from six* smaller 
stars in a cluster, called the Pleiades. Aldebaran 
and the Pleiades are in our evening sky from 
October to the last of May. 

6. This constellation has been imagined to re- 
semble a bull ; a cluster of stars, including Al- 




debaran, called the Hyades, form the face ; the 
Pleiades, the shoulders ; and other stars, other 
parts of the animal. The Bull is in the attitude 
of running furiously at Orion, who with one hand 
is striking at him with his club, and with the other 
is holding up to him his lion-headed shield. 

* This cluster is commonly known by the name of The Seven 
Stars; but only six stars can now be seen by the naked eye, and one 
of The Seven is sometimes spoken of as the lost Pleiad. 



WINTER CONSTELLATIONS. 



8 9 



7. The Pleiades, in Grecian fable, are said 
to have been daughters of king Atlas. Being 
pursued by Orion, Jupiter changed them into 
doves, and placed them in the sky. There they 
ever remain, from age to age, in one harmonious 
cluster. The meaning of the fable is, that though 
the fair daughters of love may be separated on 
earth, they shall meet again, and forever dwell 
together in the skies. Job alludes to the sisterly 
union of these stars when he says, "Canst thou 
bind the sweet influences of the Pleiades?" 



QUESTIONS. 



Relate the story of Orion. 

Describe Orion's appearance, 
as represented in the picture. 

Is there anything, in the Hea- 
vens, which resembles the 
picture ? 

Describe the constellation, as it 
appears in the sky. 

What four stars make the cor- 
ners of the square-like figure ? 

In which corner is Betelgeux ? 

In which is Saiph ? 

In which Bellatrix? 

In which Rigel ? 

Where does Orion rise ? 

Where does it pass the meri- 
dian ? 

Where does it set? 

In what months is it in our 
evening sky? 

Where is the constellation 
Taurus situated ? 



How may you know it? 
What does Aldebaran mean ? 
When are Aldebaran and the 

Pleiades in our evening sky ? 
In imagining this constellation 

to resemble a bull, what 

stars form the face ? 
What form the shoulder? 
In what attitude is the Bull 

imagined to be? 
Who were the Pleiades, in 

Grecian fable ? 
How came they to be placed 

in the sky? 
What may the meaning of the 

fable be ? 
What does Job say of the Plei- 
ades ? 
To what does the expression, 

"bind the sweet influences- 

of the Pleiades," allude? 



90 



ASTRONOMY. 



LESSON TWENTY-SECOND. 

WINTER CONSTELLATIONS— Continued. 

i. The Twins. — A good way east of Taurus, 
and northwest of Orion, appear two bright stars, 
a short distance apart, and resembling each other, 



foltux 




like twin brothers. Men in every age, looking 
up at the sky, behold them shining together, as 
though united by fraternal love. These twin 
stars are called Castor and Pollux, and the con- 
stellation, in which they are situated, is called the 



WINTER CONSTELLATIONS. 



91 



Twins. Castor and Pollux may be seen in our 
evening sky from December to July. 

2. Castor and Pollux are said to have been 
twin brothers, of whom Castor was mortal, and 
Pollux immortal. Castor having been slain, 
Pollux obtained leave of the gods to take the 
place of his brother among the dead, every other 
day. Thus they lived and died by turns. To 
reward such extraordinary affection, the gods at 
length placed them both together in the heavens. 
Go and learn from this beautiful fable a lesson 
of brotherly love. 



■Jdh 







: 




>&*& 



mmm 




92 ASTRONOMY. 

3. Leo, The Lion. — Next east of the Twins 
is the constellation of the Zodiac, called the Lion. 
It is visible in our evening sky from January to 
July. It contains three pretty bright stars, Regit- 
hcs y A I Gieba, and Dencbola. 

4. It is not easy to find any resemblance be- 
tween this constellation and a lion. Perhaps, it 
was called by the name of this fierce animal, be- 
cause it was in the sky with the sun at the season 
of raging heat. 

5. Six or seven of the stars in Leo make a 
figure resembling a sickle. It may be easily 
traced out in the sky. The bright star Regulus 
is on the end of the handle. 

6. The Greater Dog. — Southeast from Orion, 
and from us, blazes the most brilliant star ever 
seen in the heavens. It is Sirius, or the Dog 
Star. The constellation, in which it is situated, 
is called Cams Major, or the Greater Dog. 
Sirius may be seen glowing in our evening sky 
from December to July. 

7. During a part of July and August, it is over 
our heads in the daytime, and close to the sun. 
It was once imagined that, thus united with the 
sun, it produced the raging heat sometimes ex- 
perienced in these months. Hence this season is 
called the Dog Days. Now the dogs upon the 



WINTER CONSTELLATIONS. 



93 



earth, sympathizing with the dog in the sky, go 
mad with burning rage. 

8. On the picture you see the manner in which 
the stars of this constellation are imagined to 
In fact, they might as well be im- 



form a dog. 



Sirius erDogStan 




agined to form a wind-mill. Orion, that great 
hunter, having been placed in the sky, it was 
very natural to imagine his dogs and his game 
around him. Thus, in front stands the Bull, at 
his feet the Hare, and behind him his dogs ; of 



94 ASTRONOMY. 

which this is one. Below is another, called Cants 
Minor, or the Lesser Dog. 




9. The Lesser Dog. — Directly east of Betel- 
geux in Orion, and northeast of Sirius, is a very 
bright star called Procyon. It is in the constel- 
lation called the Lesser Dog. Procyon means 
before the Dog. This star is so called because it 
rises a short time before the Dog Star. It is the 
herald which announces his approach. A little 
northwest of Procyon is a smaller star called 
Gomelza. Procyon and Gomelza are situated, in 
regard to each other, very much like Castor and 
Pollux. They are visible in our evening sky from 
December till about the middle of July. 

QUESTIONS. 



1. Which way from Taurus and 

Orion are The Twins ? 
What are their names ? 
In what months may they be 

seen in our evening sky ? 

2. Relate the story of Castor and 

Pollux. 
What may be learned from this 
fable ? 



3. Which way from Virgo is the 

Lion ? 

When is it visible in our even- 
ing sky? 

What three bright stars does it 
contain ? 

4. Why was this constellation 

called the Lion ? 



CONSTELLATIONS NOT VISIBLE FROM THE U. S. 95 



5. What figure do six or seven of 

its stars make ? 
What large star on the end of 
the handle ? 

6. Which way from Orion, and 

from us, is Sirius ? 
In what constellation is Sirius ? 
In what months may it be seen 

in our evening sky ? 

7. When is Sirius overhead with 

the sun in the daytime ? 
What influence was its union 

with the sun imagined to 

have? 
What is this season called ? 

8. Does this constellation really 

resemble a dog? 
Why was it imagined to resem- 
ble a dog ? 



What stands in front of Orion ? 

What at his feet ? 

What behind him ? 

Which way from Orion and 

Sirius is Procyon ? 
In what constellation is it? 
What does the word Procyon 

mean ? 
Why was this star so called ? 
What star a little northwest of 

Procyon ? 
What stars do Procyon and 

Gomelza resemble in situa- 
tion ? 
In what months are Procyon 

and Gomelza in our evening 

sky? 



LESSON TWENTY-THIRD. 



CONSTELLATIONS NOT VISIBLE 
STATES. 



FROM THE UNITED 



i. There are many stars, in the Southern Hemi- 
sphere, which we can never see, unless we go 
there. 

2. The earth being a great globe, of which a 
great part lies between us and these stars, con- 
ceals them from our sight. 

3. We can see Rigel, Antares, and Spica Vir- 
ginis, although they are all in the Southern 



9 6 



ASTRONOMY. 



Hemisphere, beeause they are but a short distance 
over the line of the equinoctial. They are all 
stars well worth seeing. 



ERIDANUS 



• Achernar 



jfe Canepus 



outh(J\Poh 



ARGO 



Maiaplact'cfa 



SOUTHERN 
CROSS 



Sujwuta 



CENmiJB 



Constellations in the Southern Hemisphere not Visible 
from the United States. 



NEW, VARIABLE, AND DOUBLE STARS. 



97 



4. But the glories of the Southern Hemisphere 
shine too far south for our eyes. The Southern 
Hemisphere has no Pole Star, no Alrucaba ; but 
you will envy the eyes of the young astronomers 
there, when you learn that six brilliant stars, of 
the first magnitude, glow in a radiant circle 
around the Southern polar sky. Their names 
are Achernar, Canopies, Maia Placida, Alpha 
Cruets, Agena, and Btmgula. The map, page 
96, represents their relative positions around the 
Southern Pole. 

The voyager in the Southern Hemisphere al- 
ways hails with delight the vision of the Southern 
Cross. As the sign of the Christian faith, it in- 
spires the beholder with religious emotions. 

" Then came night — th' intense 
Dark blue — the burning stars ! I saw thee shine 
Once more in thy serene magnificence, 
O Southern Cross !" 



QUESTIONS. 



1. Where are the constellations 

not visible to us situated ? 

2. What conceals these constella- 

tions from our sight? 

3. What brilliant stars of the first 

magnitude, in the Southern 
hemisphere, can we see? 
Why can we see these stars 
and not see other stars in 
the Southern hemisphere ? 



How many brilliant stars of 
the first magnitude, in the 
Southern hemisphere, are 
invisible to us? 

What are their names ? 

Refer to the Map, page 96, a)id 
point out their positiojis around. 
the Southern polar sky. 



98 ASTRONOMY. 



LESSON TWENTY-FOURTH. 

NEW, VARIABLE, AND DOUBLE STARS. 

i. New Stars. — Sometimes stars suddenly 
flash forth where before there were no stars 
visible to the naked eye, and for a while continue 
to shine with great brightness, but finally dis- 
appear, and, so far as observed, nevei return. In 
two thousand years, only twenty-one such stars 
have been observed. 

2. These stars are called new stars. Some- 
times they are called temporary stars, since they 
appear only for a time. They have no names, 
neither are they counted in the number of the 
stars. 

3. The most remarkable of all such stars was one 
observed in the constellation Cassiopeia, by that 
great astronomer, Tycho Brahe, a little over three 
hundred years ago. It was brighter than Jupiter 
or Sirius, or even Venus, and was visible in broad 
daylight. In a little less than a year and a half, 
it totally disappeared, and has not been seen 
since. 

4. Another such star was observed by that 



NEW, VARIABLE, AND DOUBLE STARS. ' 99 

great astronomer, Kepler, about two hundred and 
eighty years ago, situated in the constellation 
called The Serpent- Bearer. It was brighter 
than Jupiter, but not quite so bright as Venus. 
At the end of about fifteen months, it could be 
no longer seen without a telescope. Another 
such star appeared in 1848, and another in 1866. 

5. Astronomers do not think that these new 
stars, so called, are really new — that is, just 
created, when they appear. Neither do they 
think that when they disappear, they become 
extinct. 

Astronomers think that certain changes in the 
matter of which they are composed, and perhaps 
also in the matter through w^hich light passes 
from them to us, cause this sudden splendor and 
its cessation. 

6. Variable Stars. — There are many stars 
whose brightness varies ; hence they are called 
variable stars. It is estimated that there are 
between one hundred and fifty and two hundred 
such stars. Perhaps there are many more, as 
observers are from time to time discovering new 
ones. 

Instead of suddenly flashing forth with great 
brilliancy, like the new or temporary stars, they 
are observed to grow brighter and brighter 



IOO ASTRONOMY. 

gradually, until a certain period, when they begir 
to grow gradually less and less bright, and finally 
become as they were at first, or entirely disap 
pear. Some stars exhibit this appearance only 
for a few days, others for many years. 

7. The variable star Mira, in the constella 
tion called the Whale, is as bright as a star 01 
the second magnitude for about two weeks. 
Then it decreases in brightness for about three 
months, when it becomes invisible to the naked 
eye. In about five months, it becomes again 
visible, and in about three months more, it is as 
bright as ever. It is a wonderful star. Hence 
its name Mira. Mira means Wonderful. 

8. The star Algol, in the constellation Perseus, 
for about two days and a half, appears to be a 
star of the second magnitude. Then its bright- 
ness decreases until it appears as a star of the. 
fourth magnitude. In about twenty minutes, it 
begins to grow bright again, and continues to do 
so for about four hours, when it appears, as at 
first, to be a star of the second magnitude ; and so 
it continues to vary perpetually. 

9. Double Stars. — Many stars which, when 
seen with the naked eye, appear to be only one 
single star, are discovered, when seen through the 
telescope, to be really two or more stars. They 
are so close together, that the naked eye, unable, 



NEW, VARIABLE, AND DOUBLE STARS. IOI 

at their great distance from us, to distinguish 
between them, sees them as one object. These 
stars, when only two in number, are called Dou- 
ble Stars. 

10. About eighty years ago only four such 
stars had been observed. Now the number ob- 
served, including stars visible only through the 
telescope, is about six thousand. 

Generally, one of the two stars is larger than 
the other. Astronomers have discovered that 
some of the double stars revolve, one around the 
other, and have computed the time occupied by 
some of them in such revolution. 

1 1. These double stars are frequently of differ- 
ent colors, of many delicate and beautiful shades, 
in harmonious contrast. 

12. Siriusisthe largest double star. Mr. Clark, 
with his great telescope, first discovered that he 
had a little companion star, not very far from him. 
The Pole Star, the stars Castor and Rigel, are 
other instances of double stars. 

Imagine these double stars, always revolving 
one about the other, obedient to the command 
of their Great Creator, and shining for each other, 
in all their varied, rich, and contrasted colors. 
Wonderful companionship of the Heavenly 
Bodies ! God has made even the stars for each 
other ! 



102 



ASTRONOMY. 



QUESTIONS. 



1. Do stars sometimes appear 

where before there were no 
stars visible to the naked 
eye ? 

Describe the manner in which 
these stars appear and dis- 
appear. 

How many such stars have 
been observed in two thou- 
sand years ? 

2. What are these stars called ? 
Have they any names? 

3. Who observed the most re- 

markable of such stars ? 

How long ago did Tycho 
Brahe observe this star? 

In what constellation was it? 

Describe its appearance. 

How long before it totally dis- 
appeared ? 

Has it ever returned ? 

4. What great astronomer dis- 

covered another such star ? 

In what constellation was it 
situated ? 

How long since Kepler dis- 
covered this star? 

Describe its appearance. 

How long before it became 
invisible to the naked eye ? 

How recently have such stars 
appeared ? 

5. Do astronomers think that 

such stars are really new, or 
that they become extinct 
when they disappear? 
What, do astronomers think, 
is the cause of their sudden 
splendor and of its cessa- 
tion ? 



6. What are variable stars ? 
How many variable stars are 

there ? 
How do they differ from new 

or temporary stars ? 
How long is the period of 

their variation ? 

7. Describe the variation of the 

star Mira, in the constella- 
tion called the Whale? 

Why is this star called Mira? 

What does the word Mira 
mean ? 

8. Describe the variation of Al- 

gol, in the constellation 
Perseus. 

9. What stars are called double 

stars? 

10. Eighty years ago, how many 

such stars had been ob- 
served ? 

What is the number now? 

What is the magnitude of 
double stars, when com- 
pared with each other? 

What motion have such stars 
been observed to have ? 

Has the time occupied in such 
revolution been computed ? 

11. Are double stars of the same, 

or of different colors? 

12. Which is the largest of the 

double stars ? 
Who discovered that Siriu? 

has a companion star? 
How did Mr. Clark discover 

this? 
Name some other instances of 

double stars. 



COLORED STARS. 103 

LESSON TWENTY-FIFTH. 

COLORED STARS. 

i. " In a transparent atmosphere," says Schellen, 
"especially in a southern clime, the stars do not 
all appear with the white brilliancy of the dia- 
mond : here and there the eye discovers richly- 
colored gems, sparkling on the sombre robe of 
night, in every shade of red, green, blue, and 
violet." 

With the aid of the telescope, these colors can 
be seen more clearly. 

2. The stars, viewed as single stars, are of dif- 
ferent colors. Some are white, some red, some 
orange, some yellow, some green, with many 
varieties of delicate and exquisitely beautiful 
shades. For example: Aldebaran, Antai'es, and 
Betelgeux are red ; Vega and Struts are white ; 
Arcturtis, Procyon, and Pollux are yellow. 

3. Some stars have changed their color. 
Sirius was once red, but is now white ; Capclla 
was once red, but is now blue. 

4. The contrast between the colors of the 
double stars, or companion stars, is exceedingly 
beautiful. The following are examples : yellow 



104 ASTRONOMY. 

and purple, pale green and blue, orange and 
sea green, white and light purple, orange and 
emerald green, yellow and sapphire, blue, green, 
and bright blue. 

It has been observed that the smaller star of 
the two companions has generally the more deli- 
cate color. 

It must not be supposed that all double stars 
have different colors. Many such stars have 
the same color. 

5. We do not know, that all the double stars 
are companion stars, or have any special relation 
to each other. Perhaps only the pairs which 
are of different colors are companion stars. I 
venture this suggestion, because these different 
colors seem to have been suited to each other. 

6. Astronomers think that the different colors 
of the stars depend upon the nature of the matter 
of which they are composed, or by which they 
are surrounded, whence the light comes to us. 
As this matter changes, so also the color of the 
stars changes. 



1. Where and under what circum- 

stances do the stars appear 
to be of different colors ? 

2. Enumerate some of these col- 



QUESTIONS. 

What is the color of Antares, 
Aldebaran, and Betelgeux? 

What is the color of Vega and 
Sirius ? 



NEBUL/E. 10 = 



What is the color of Arcturus, 

Procyon, and Pollux? 
Specify some stars which have 

changed their color. 
Specify some of the contrasted 

colors of the double stars, or 

companion stars. 



Have all double stars different 
colors ? 

5. Do we know that all double 

stars are companion stars ? 

6. What do astronomers think the 

different colors of the stars 
depend upon ? 



LESSON TWENTY-SIXTH. 

NEBULA. 

i. Nebula is a Latin word, and means mist. 
In astronomy it means a whitish, misty spot on 
the sky. Look up in a clear night, when the 
moon is not shining, and you will see such spots 
in different parts of the Heavens. 

2. Only a few nebulce can be seen with the 
naked eye. With a telescope you can see many 
thousands. They are of many different shapes. 
Some are circular; some annular — that is, 
ring-shaped ; some spiral — that is, shaped like a 
corkscrew ; some crab-shaped, and many of very 
irregular form. The figures on pages 106 and 107 
represent nebulce of different forms. 

3. The Milky Way — that white, luminous belt, 
which you see so clearly in a clear night, when 
the moon is absent, running across the Heavens, 



io6 



ASTRONOMY. 




Annular Nebula. 



Planetary Nebula. 




Spiral Nebula. 



Crab-shaped Nebula. 



NEBUL.E. IO7 

northeast and southwest, from horizon to horizon, 
— is one great nebula. 

4. Two white spots in the Southern Hemi- 
sphere, near the South Pole, visible to the naked 




Globular Nebula. 



eye, but not visible in the United States, called 
the Magellanic Clouds, are great nebuhc. 

5. To the naked eye, the ncbulce are merely 
white spots ; but examine them with a telescope, 
and you will see that they are composed of innu- 



108 ASTRONOMY. 

merable small stars, lying so close together that 
their combined light spreads a soft, mistv white- 
ness over the sky. 

It is not necessary to suppose that these stars 
are in fact small. Their apparent smallness may 
be owing, in whole, or in part, to their great dis- 
tance from us. Like all the fixed stars, they are 
regarded as suns to other systems. 

6. There is a remarkable nebula in the constel- 
lation Orion, situated in that part called the 
Sword-Belt. Part of it is visible to the naked 
eye. You may look for it when it is clear and 
there is no moon. A part of it can be seen only 
through a telescope. 

7. You must not suppose that all nebulcz are 
composed of clusters of stars. 

Astronomers have not been able, with the tele- 
scope, to discern stars in all of them. This may 
be because the stars are so distant that even the 
telescope has not power to reach them. But 
astronomers have discovered, by means of an 
instrument called the spectroscope, that some 
nebulcz are composed of gas. This instrument 
shows the colors of the light coming from the 
nebulcz to be the same as the colors of gases well 
known to us. Hence it is concluded that the 
matter from which these colors come is gas. 



NEBULAE. 



109 



QUESTIONS. 



1. What does the word nebula 

mean ? 

What does it mean in astron- 
omy ? 

Under what circumstances can 
you see nebula in the sky ? 

2. Can you see many with the 

naked eye ? 
How many can you see with 

the telescope ? 
Are nebulce all of one shape, or 

are they of many different 

shapes ? 
Mention some of their different 

shapes. 

3. What great nebula runs across 

our sky from horizon to 
horizon ? 

4. What great nebulce are there 

in the Southern hemisphere 

near the South Pole ? 
Are these nebulce visible to the 

naked eye ? 
Are they visible in the United 

States ? 

5. How do nebulce appear to the 

naked eye ? 



What are they found to be, 
when examined through a 
telescope ? 

Are the stars in the nebula 
really small ? 

To what may their apparent 
smallness be owing ? 

What are these stars considered 
to be? 

There is a remarkable nebula 
in Orion. In what part of 
the constellation is it situ- 
ated ? 

Is this nebula visiDie to the 
naked eye ? 

Are all nebulce composed of 
clusters of stars ? 

Have astronomers been able, 
with the telescope, to dis- 
cover stars in all of them ? 

To what may this failure to 
discover stars be owing ? 

What does the spectroscope 
show that some nebula are 
composed of ? 

How does the spectroscope show 
this? 



110 ASTRONOMY, 

LESSON TWENTY-SEVENTH. 

THE FIXED STARS ARE SUNS. 

1. Perhaps the fixed stars are suns in the skies 
of worlds like our Earth. Could you mount 
upon wings of lightning, and fly to some world 
near Sirius, you might behold him blazing in its 
sky, even larger and brighter than our Sun to us, 
while our Sun, should you be able to see it, would 
seem a faint glimmering star, among thousands 
of others. 

2. I have two reasons for believing Sirius to 
be a sun. First; it is is immensely large. The 
Sun, which seems a round, bright spot upon the 
sky, no larger than your hat-crown, is in reality 
a vast globe, able to hold, were it hollow, hun- 
dreds of thousands of worlds like our Earth, with 
all their oceans, their continents, their islands, 
and their mountains. But astronomers have 
found that Sirius is four times as large as our 
Sun. A body so vast was never made just to 
twinkle, a little brilliant spot, upon our evening 
sky. 

3. Second : not only is Sirius immensely large, 



THE FIXED STARS ARE SUNS. I I I 

diet its light, like 07tr Situs, is not borrowed ; it is 
its own. I will show you how we know this. 
Sirius is very, very far from us — so far that the 
telescope which shows mountains and shadows on 
the moon, will not make it look any larger. So 
immensely distant is it, that light, which comes to 
us from the Sun in eight minutes, requires three 
years to come from Sirius. Feeble, borrowed 
light like the moon's could never perform a 
journey of three years ; its strength would be 
spent long — long before it could reach the 
Earth. An immense globe of light, such as 
Sirius is — what can it be but a sun to other 
worlds ? 

4. If Sirius be a sun, the other fixed stars may 
be suns too. Arcturus, Aldebaran, Altair, An- 
tares, Betelgeux, Rigel, Capella, Lyra, Procyon, 
Sirius, Fomalhaut, Achernar, Canopus, Maia 
Placida, Agena, Bungula, imagine each a vast 
globe of flame — a sun glowing in the sky of 
many a world. Behold the Dippers, and Cassio- 
peia, and the Twins, and the Bull, and the Lion, 
and the Southern Cross, each a constellation of 
suns, and each sun enlightening many a vast 
world. Observe the Pleiades — a cluster of suns ; 
cast your eye all over the starry heavens, and 
behold in its thousands of stars thousands of 



112 



ASTRONOMY. 



suns, enlightening tens of thousands of worlds. 
Turn then to the Milky Way and the nebulae, — 
so thick-set with suns. Finally, raising your 
thoughts above the stars, think of Him who was 
able to make all these vast globes of flame, and 
the countless worlds around them. 



QUESTIONS. 



1. What may the fixed stars be ? 
If you could fly to some world 

near Sirius, how might he 
there appear ? 
How would our Sun appear? 

2. How many reasons have you 

for believing the fixed stars 

to be suns ? 
Mention the first. 
How many worlds like the 

Earth is the Sun large enough 

to hold? 
How much larger than the Sun 

is Sirius ? 



Was a body so vast made for 

nothing but to twinkle in our 

sky ? 
Mention a second reason for 

thinking Sirius to be a sun. 
How do we know that Sirius' 

light is not borrowed light ? 
What could such an immense 

globe of light have been 

made for ? 
If Sirius be a sun, what may 

we suppose the other fixed 

stars to be? 



LESSON TWENTY-EIGHTH. 

COMETS. 

I. There sometimes suddenly appear in our 
sky bodies with a bright, star-like head, called 
the nucleus, from which streams forth a long, 
bushy tail of light, somewhat in the manner of 



COMETS. 



113 



loose, floating hair. These are Comets; the 
word Comet means long-haired. They seem like 
visitors; for, after a few days, or at most 
months, they depart, — perhaps, never to return. 

Some comets are not visible to the naked eye, 
and can be seen only through a telescope. Others 




have been seen with the naked eye, in broad day- 
light. 

2. No one can tell you in what part of the 
sky to look for comets. The paths of the 
planets, you remember, pass east and west, and 
always in that part of the sky through which the 



114 ASTRONOMY. 

Sun seems to move ; but comets may appear any 
where — in the north or in the south, in the east 
or in the west. They seem to roam at will, 
being confined to no one region of the heavens. 

3. Neither can any one tell how large a comet 
will appear. Some comets have been seen with 
a head no larger than a small star ; others have 
looked as large as Venus, and it is said that there 
have been comets as large as the moon. Even 
the same comet does not always appear equally 
large. At first, it generally grows larger and 
brighter, and then smaller and fainter until it is 
gone. 

4. Nor is it possible to tell how long a comet's 
tail will be. Of some, the tail is short — of others, 
pretty long — and of others, immensely long. 
About one hundred and fifty years ago, a comet 
appeared whose tail reached from the horizon to 
the very top of the sky ; and about one hundred 
and thirty years after our Saviour, there was one 
whose tail was long enough to reach from one 
side of the heavens to the other, like the Milky 
Way. For many years, however, the comets have 
been short-tailed. The tail of the same comet 
does not always appear equally long. At first it 
generally grows longer and brighter, and then 
shorter and fainter, until it disappears. 



COMETS. 1 1 5 

5. Indeed, comets are the most capricious 
beings imaginable ; it is not even possible to tell 
how many tails they will have, nor whether the 
tail will go before or follow after the head. Most 
comets have but one tail ; but about a hundred 
and fifty years ago, there appeared a comet with 
six tails, spreading out like an immense fan ; and 
one is mentioned as having been seen with both 
a tail behind and a tail before. 

6. Comets are under no more control, in regard 
to their apparent motions, than in regard to the 
place of their appearance, their size, or the length 
and number of their tails. Some move from east 
to west, others from west to east ; some from north 
to south, others from south to north ; some go 
straight forward, others with a crooked, snake- 
like course ; some move fast, others slow. Even 
the same comet moves faster at some times than 
at others. It is hard to tell where to look for a 
comet ; and if you find it to-day, you do not 
know where it will be to-morrow. 

7. Of some eight hundred and eighty comets 
which have appeared in our sky, been observed, 
recorded, and disappeared, only about twenty are 
known to have returned. 

Of these, one disappears and returns in about 
three years, three in five, one in seven, one in 
thirteen, and one in seventy-five years. 



u6 



ASTRONOMY. 



8. Once it was thought, when a comet ap- 
peared, there would soon be war, or pestilence, 
or famine ; and men have trembled at the sight 
of a comet, for fear the world would be destroyed, 
But of the eight hundred and eighty comets, 
which have been seen, not one is known to have 
excited men to fight, or to have made them sick, 
or to have killed their corn ; and as for the world, 
it yet remains unharmed. Should the tail of a 
comet strike the earth, it is not certain that it 
would do any injury, for comets seem to be made 
of matter even lighter than the clouds, since stars 
have been seen shining through them. 



QUESTIONS. 



1. How do comets look ? 

What does the word co??iet 
mean ? 

Why do comets seem like visi- 
tors to our sky ? 

2. In what part of the sk)^ must 

you look for comets ? 

3. How large do comets appear ? 
Does the same comet appear 

always equally large ? 

4. How long are the tails of 

comets? 

Two comets are mentioned 
which had very long tails; 
how long were they ? 

Are the comets now long- 
tailed or short-tailed ? 

Does the tail of the same comet 
appear always equally long ? 



tails do comets 



5. How many 

have ? 
Does the tail go before or after 
the head ? 

6. Which way and how do comets 

move ? 

7. How many comets have visited 

our sky ? 
How many of them are known 

to have returned ? 
Mention the periods of their 

return. 

8. What was it once thought would 

soon happen, when a comet 
appeared ? 
If the tail of a comet should 
strike the earth, would it do 
any hurt? 



THE SOLAR SYSTEM. 117 

LESSON TWENTY-NINTH. 

THE SOLAR SYSTEM. 

i. The planets, as I have already told you, are 
great worlds, receiving light and heat from the 
Sun, while the fixed stars are themselves suns to 
other worlds, and so very far from our Sun that 
he cannot appear, at them, larger than a star. 

2. The Sun, with the planets and their moons, 
composes, as it were, a regular family, or system. 
Astronomers call it the System of the Sun, or 
the Solar System. They do this to distinguish 
it from other systems of worlds, of which they 
suppose there are as many as there are fixed 
stars, or suns, to enlighten and warm them. 
Thus, there may be the system of Sirius, the 
system of Arcturus, and so on — as many systems 
as there are fixed stars, or suns. 

3. The names of the planets, known to us, 
are Mercury, Venus, the Earth, Mars, Jupiter, 
Saturn, Herschel or Uranus, and Neptune. 
Besides these, are the Asteroids, Juno, Vesta, 
Ceres, Pallas, and the others, about two hundred 
and forty in number, all discovered within the 



Il8 ASTRONOMY. 

last one hundred years, and all named by their 
discoverers. 

4. The Earth has one moon, Mars two, Jupiter 
four, Saturn eighty Herschel or Uranus six, 
Neptune one. Thus, we know that there are 
twenty-two moons in the Solar System. Others 
may yet be discovered. We also know that, 
including the eight planets and the twenty-two 
moons, there are thirty heavenly bodies in the 
Solar System, besides the Sun, the asteroids, 
and the comets. 

5. These eight planets, as you know, all re- 
volve in great orbits around the Sun, and these 
twenty-two moons revolve about the planets to 
which they belong, and accompany them in their 
revolution around the Sun. The asteroids also 
revolve around the Sun, in orbits lying near 
together. 

6. You will observe that the planets, with 
reference to their moons, are called primaries, 
and that the moons, with reference to the planets 
around which they revolve, are called secondaries, 
or more generally satellites — that is, attendants,, 
because they seem to wait on their primaries, 
serving them with their beautiful light. 

7. Astronomers have discovered that the plan- 
ets are arranged around the Sun,* as represented 



THE SOLAR SYSTEM. II9 

on the picture of the Solar System, page 131. 
Observe it. You see the Sun in the centre ; 
nearest to him Mercury, next Venus, next the 
Earth ; then come Mars, the Asteroids, then 
Jupiter, Saturn, Herschel or Uranus, and, most 
distant of all, Neptune. 

Mercury, the planet nearest the Sun, is not, as 
it seems in the picture, very near to him. It is 
many millions of miles from him. 

8. Astronomers have ascertained how large the 
Sun is. He is by far the largest of all the bodies 
of the Solar System. He is as much larger than 
the Earth as a ball, as large as a man can reach 
around with both arms, is larger than a pea. 
How very far from us he must be, to appear no 
larger than he does ! 

9. The Sun, as you have learned, seems to 
move through the sky every day, and also to be 
continually moving north and south the whole 
year. But there are many reasons for believing 
that it is the Earth and not the Sun which 
moves. How strange it would appear to see a 
ball, as large as a man can reach around, revolving 
about a pea ! 

But while the Sun remains in one place,* send- 

* I mean that the Sun does not move, so far as regards the planets 
and other bodies which compose the Solar System. Astronomers 



120 



ASTRONOMY. 



ing forth light and heat to all the planets, he 
revolves, like a wheel on its axis, once every 
twenty-five days. * 



QUESTIONS. 



1. What are the planets? 
What are the fixed stars ? 
How far from the Sun are the 

fixed stars ? 

2. What bodies compose the Solar 

System ? 
Why do astronomers call it the 

Solar System ? 
How many other systems of 

worlds do they suppose there 

are ? 

3. What are the names of the 

planets known to us ? 
How many asteroids have been 

discovered ? 
Have they been named ? 
By whom ? 

4. How many moons has the 

Earth ? 
How many has Mars ? 
How many has Jupiter? 
How many has Saturn ? 
How many has Herschel ? 
How many has Neptune ? 
How many moons in all, do we 

know, there are in the Solar 

System ? 



May others yet be discovered ? 

Including the eight planets 
and the twenty-two moons, 
how many heavenly bodies 
are there in the Solar Sys- 
tem ? 

What other bodies are included 
in the Solar System ? 

How do these eight planets 
and their twenty-two moons 
revolve ? 

How do the asteroids revolve ? 

What are the planets, with 
reference to their moons, 
called ? 

What are the moons called, 
with reference to their plan- 
ets ? 

What name is more generally 
used, when speaking of the 
moons, with reference to 
their planets? 

What does the word satellite 
mean ? 

Why are the moons called 
satellites or attendants ? 



have discovered that the Sun and the whole Solar System have an 
independent motion in space. So also have the fixed stars. 

* Astronomers have learned this by observing black spots gradually 
move across the Sun, disappear, and in twenty-five days from the 
time when first observed, appear again in the very spot from which 
they started. 



THE SOLAR SYSTEM. 



I2T 



Which of the heavenly bodies 

is the centre of the Solar 

System ? 
Which of the planets is nearest 

to him ? 
Which next ? 
Which next ? 
What planet, after the Earth, is 

next nearest to the Sun ? 
Mention the three planets next 

nearest, in the order of their 

distances ? 
Which planet is farthest from 

him of all ? 



Which is the largest body in 

the Solar System ? 
How much larger than the 

Earth is the Sun ? 
Does the Sun really move 

through our sky ? 
What makes him appear to 

move? 
Can you mention any reason 

for believing that the Sun 

does not move around the 

Earth ? 
How often does the Sun re- 
volve on his axis ? 



LESSON THIRTIETH. 



THE SOLAR SYSTEM— Continued. 

i. The Earth. — Strange as it may seem to 
you, this great globe, the Earth, with its green 
continents and islands, and its blue ocean, ap- 
pears at the other planets, as they do to us — a 
little bright star. It is a planet as much as Jupi- 
ter or Venus, or any other one ; for it is round 
like them, lighted by the Sun like them, and re- 
volves like them. 

2. The Earth revolves on its axis from west to 
east once every twenty-four hours — presenting 
its different sides one after another to the Sun. 
In this way it makes the Sun, moon, and stars 



122 ASTRONOMY. 

appear to move from east to west over our heads ; 
and in this way, too, the countries on its different 
sides have each their turn of day and night. 

3. The Earth has another motion : while it is 
continually revolving like a wheel on its axis, it 
is at the same time travelling, from west to east, 
in a great circuit round the sun. This circuit, or 
orbit, as it is called by astronomers, you see rep- 
resented on the picture of the Solar System. The 
time, which the Earth takes to go round the Sun, 
is called a year. It is this motion of the Earth 
in its orbit which makes the apparent annual 
motion of the Sun and of the stars which I have 
already described. Perhaps you wonder that you 
do not feel the Earth's motion. It is because 
the motion is so easy — there is nothing for the 
Earth to strike against and jolt you. The moon 
revolves from west to east round the Earth, and, 
at the same time, moves forward to keep com- 
pany with the Earth, in its motion round the 
Sun. 

4. All the other planets are immense globes, 
some of them larger and some smaller than the 
Earth. All of them revolve, as though hung on 
an axis, like the Earth, some in a longer and 
some in a shorter time — and all of them travel, 
like the Earth, in great orbits round the Sun. 



THE SOLAR SYSTEM. 1 23 

See the paths or orbits of the planets \ represented 
on the picture. 

5. Jupiter is the largest of all the planets. 
Let us represent him by a moderate-sized orange ; 
then a small orange will represent Saturn, the 
next largest ; a plump, round cherry will repre- 
sent Herschel ; Neptune is a little larger than 
Herschel. Two peas will represent Venus and the 
Earth ; a large pin's head, Mars ; a grain of mus- 
tard seed, Mercury — and grains of sand will 
represent Juno, Vesta, Ceres, Pallas, and the 
other asteroids. Our moon, which appears 
almost as large as the Sun, is in reality not so 
large as Mercury, the smallest of all the planets 
visible to the naked eye. She appears large be- 
cause she is near us. 

6. The Earth is so far from the Sun that, if you 
should fly day and night, as swift as a cannon- 
ball, you could not reach the Sun in eleven years. 
Mercury is about three times nearer the Sun than 
the Earth, Venus a little more than twice the dis- 
tance of Mercury, Mars considerably less than 
twice the distance of the Earth, Jupiter about 
five times, Saturn about nine times, Herschel or 
Uranus about nineteen times that distance, and 
Neptune about twice as far from the Sun as Her- 
schel. 



124 



ASTRONOMY. 



7. The planets nearest the Sun require more 
time to revolve on their axes, and less time to go 
around the Sun, than those farthest from him. 
Those nearest have the longest day, and those 
farthest off the longest year. Mercury, Venus, 
the Earth, and Mars have about twenty-four 
hours, each, for their day, and Jupiter and Saturn 
not half so many. Mercury's year is about one 
fourth as long as ours ; Venus' about three 
fourths, Mars' almost twice -as long. Jupiter's 
year is equal to twelve, Saturn's to thirty, Her- 
schel's to eighty-four, and Neptune's to one hun- 
dred and sixty-four, of our years. 

8. You cannot understand in what way many 
of the things which I have told you in this lesson 
have been discovered, until you advance farther 
in the study of Astronomy. 



QUESTIONS. 



1. How does the Earth appear at 

the other planets ? 

Is the Earth a planet like Jupi- 
ter or Venus ? 

What makes you think it to be 
a planet? 

What makes the Sun, moon, 
and stars appear to move 
over our heads through the 
heavens ? 

2. How often does the Earth re- 

volve on its axis ? 



Which way does it revolve ? 
What other motion has the 

Earth ? 
What do astronomers call the 

path in which the Earth 

travels round the Sun ? 
What is a year ? 
What effect has this motion of 

the Earth upon the Sun and 

fixed stars ? 
While the Earth thus travels 



THE SOLAR SYSTEM. 



125 



round the Sun, what be- 
comes of the moon ? 

4. What is the shape and size of 

the other planets ? 
In what respects are they like 
the Earth ? 

5. Which is the largest of all the 

planets? 

If we represent Jupiter by a 
moderate-sized orange, what 
" will represent the other 
planets ? 

How large is our moon com- 
pared with the planets ? 

Why does she appear so large ? 

6. If you should fly day and night, 

swift as a cannon-ball, how 
long would it take you to 
reach the Sun ? 
Which planet is nearest the 
Sun? 



How much nearer to him is it 
than the Earth ? 

How much farther off is Jupi- 
ter, Saturn, and Herschel? 

Which planets require the most 
time to revolve on their 
axes ? 

Which require the longest time 
to go round the Sun ? 

Which have the longest day ? 

Which the longest year ? 

How long is the day of Mer- 
cury, Venus, and the Earth ? 

How long is that of Jupiter 
and Saturn? 

How long is Mercury's year ? 

How long is Venus' ? 

How long is Mars' ? 

How long Jupiter's, Saturn's, 
and Herschel's ? 

How long is Neptune's ? 



LESSON THIRTY-FIRST. 



THE SOLAR SYSTEM— Continued. 



Rotation and Revolution of the Planets. — Their Cause 
and Effects. 

i. Of those silent, mysterious forces which 
cause the planets to revolve on their axes, and 
hold them, and carry them, in their orbits around 
the sun, I have said nothing. The subject is 
difficult for beginners. 



126 ASTRONOMY. 

2. Look at the picture of the Solar System, 
page 131, and imagine to yourselves thirty planets, 
revolving on their axes, including twenty-two 
moons revolving about their primaries, and all 
revolving around the sun. Observe too, that of 
the twenty-two moons, each revolves around its 
primary, in the same period of time, and that 
each planet always performs its revolution on its 
axis, in the same number of hours, and its revo- 
lution around the sun, in the same number of 
days or years. 

Whence this unerring, measured movement of 
the heavenly bodies, without collision, each, in 
its own orbit, and in its own time, so harmonious 
that it has been likened to music, — sometimes 
called the Music of the Spheres? 

Addison speaks of the stars as singing. He 
says : 

" What though nor real voice nor sound 
Amid their radiant orbs be found? 
In Reason's ear they all rejoice, 
And utter forth a glorious voice, 
Forever singings as they shine, 
1 The hand that made us is divine.' " 

It is to these harmonious movements that Kep- 
ler refers, when he says : 

" Praise ye the Lord, ye Heavenly Harmonies." 



THE SOLAR SYSTEM. \2J 

3. Beginners though you are, you will ask me, 
What is the cause of these wonderful motions ? 
Why do the planets turn on their axes ? Why 
do they move in such majestic, harmonious meas- 
ure around the sun ? I answer : 

The Almighty Hand that made them created 
two forces — one which set them in motion in a 
straight line, called the Projectile Force, and the 
other, called the Force of Gravitation, which em- 
braced them the very instant they began to move, 
changed the straight line into a curve, and so 
carried them, and ever carries them, in perpetual 
revolution on their axes, the moons around their 
planets, and both moons and planets around the 
sun. This you may not fully understand now ; 
but it will become clear to you as you advance in 
the study of Astronomy. 

4. The Projectile Force, in kind, is like that 
which a boy gives his ball when he throws it. 
The moment that the ball leaves his hand to move 
off in a straight line, the Force of Gravitation, 
which draws all matter upon the earth towards 
its centre, lays hold of it, bends the straight line 
into a curve, until the ball reaches the ground. 

To compare great things with small, in like 
manner the Almighty Hand first set the planets 
in motion, in a straight line, by a projectile im- 



128 ASTRONOMY. 

pulse, which line, without revolving on their 
axes or around the sun, they would have pur- 
sued forever, had not the same Almighty Hand, 
at the same instant, arrested their progress by 
the Force of Gravitation, changed the direction 
of their motion into a curve, and thus compelled 
them to turn on their axes in perpetual rotation, 
and at the same time to move in perpetual revo- 
lution, in great orbits, around the common cen- 
tre. The combined action of these two forces, 
constituting one force, in constant operation, is 
the answer to your question. 

5. Kepler learned to measure the Force of 
Gravitation, but did not know that it was of the 
same nature as that which attracts bodies on the 
earth to its centre. About fifty years later the 
great Sir Isaac Newton made that discovery. Ob- 
serving an apple fall from the tree to the ground, 
he conceived the idea, as if by a sublime inspira- 
tion, that the force which attracted the apple ex- 
ists everywhere in the material universe, and is the 
cause of all the motions of the heavenly bodies, 
— an idea now universally admitted to be true. 

6. To the rotation of the earth on her axis, 
and to the revolution of the moon around the 
earth, I need not say, are due all the wonderful 
phenomena of light, in all its manifold variations, 



THE SOLAR SYSTEM. 1 29 

from the blackness of midnight to the splendor 
of noonday — from the freshness and beauty of the 
morning dawn to the calm glories of the evening 
sunset. You are familiar with these phenomena, 
so familiar that, perhaps, you do not often think 
whence they come. 

7. I have explained to you, in Lesson Third, 
how the revolution of the earth in her orbit 
around the sun causes the seasons of the yean 
This orbit is so marked out by the Great Creator, 
that the earth, as she moves through it, always 
presents her surface to the sun so as to receive his 
beneficent rays in the exact measure necessary for 
summer or winter, spring or autumn. During a 
part of her course, her position with reference 
to the sun is such, that his rays come to her full 
and direct, and during a part such, that they come 
to her obliquely and scattered. See the figure y 
page 13. 

8. In the rotation of the earth upon her axis, 
and in her revolution in the great pathway or- 
dained for her, lies the fulfilment of the promise 
in Genesis viii.: 

"While the earth remaineth, seedtime and harvest, cold and heat, 
summer and winter shall not cease." 

What is true of the earth, it would seem must 
be true of the other bodies like her, in the Solar 
System. 



130 



ASTRONOMY. 



QUESTIONS. 



i. -2. How many planets in the 
Solar System ? 

How many of them are prima- 
ries ? 

How many of them axe second- 
aries ? 

Do both the primaries and the 
secondaries revolve on their 
axes and around the sun ? 

What planet revolves around 
the earth, and at the same 
time around the sun ? 

Is it a primary, or a secondary? 

What has the harmonious 
movement of the heavenly 
bodies in the Solar System 
been likened to ? 

Addison speaks of the stars as 
singing; recite his lines. 

To what does Kepler refer, 
when he calls upon the 
Heavenly Harmonies to 
praise the Lord ? 
3. What makes the planets in the 
Solar System turn on their 
axes ? 

What makes them revolve 
around the sun ? 

What makes the moon revolve 
around the earth ? 

What is a pi'ojectile force ? 

In what kind of line does it 
cause a body to move ? 

In what line will a body pro- 
jected move, when attracted 
by the force of gravitation ? 



Give an example of projectile 
force. 

In order to arrest the action of 
a projectile force, and carry 
the body round in a curve, 
towards what point must the 
force of gravitation attract 
it? 

Who measured the force of 
gravitation, before its nature 
was known ? 

How long afterward before its 
nature was discovered ? 

Who discovered it? 

How did the idea of its nature 
occur to Sir Isaac Newton ? 

What idea as to the cause of 
the motions of the heavenly 
bodies did the fall of the 
apple suggest ? 

Is this idea now universally 
admitted to be true? 
-7. To what cause are the phe- 
nomena of light due ? 

What causes the seasons of the 
year? 

Recite the promise in Genesis 
viii. 

In what does the fulfilment of 
this promise consist? 

Do the same causes, which pro- 
duce day and night and the 
seasons on the earth, have 
the same effect on the other 
heavenly bodies in the Solar 
System, which are like the 
earth ? 



THE SOLAR SYSTEM. 



131 




The Solar System. 



132 ASTRONOMY. 

LESSON THIRTY-SECOND. 

HISTORY OF ASTRONOMY. 

In the earliest ages of the world, men were 
very ignorant of Astronomy. They thought that 
the earth was a vast plain, above which the hea- 
vens were spread out like a tent. 

When the sun disappeared in the west, they 
imagined he had gone down to bathe and to 
sleep in the ocean, from which he came forth 
again in the morning, in the east. The moon 
and stars, as they supposed, did the same. Some 
thought that the stars were divine beings ; others, 
that they were the abode of such beings. 

Some Greek philosophers believed that the 
stars were made of air and fire ; others, that they 
were solid bodies surrounded by fire. One of 
them thought that the sun was a great, red-hot 
stone. 

Some taught that the sun, moon, and earth 
were flat ; others, that they were cylindrical. A 
few, like Anaximander and Anaxagoras, enter- 
tained more correct opinions. 

Pythagoras secretly taught the diurnal and the 



HISTORY OF ASTRONOMY. 1 33 

annual motion of the earth, but dared not declare 
his opinions openly, for fear of the people. 

Ptolemy, a very distinguished Greek Astrono- 
mer, lived about seventy years after our Saviour. 
He taught that the earth was at rest, while the 
sun, moon, and stars revolved round it. This 
doctrine was generally believed until the time 
of Nicolas Copernicus — more than a thousand 
years. 

Nicolas Copernicus, a Prussian, lived about 
three hundred and fifty years ago. This man re- 
linquished the study of medicine, to devote his 
life to the study of Astronomy. He wrote a 
book entitled The Revolutions of the Heavejily 
Orbs, in which he showed that the sun and fixed 
stars were at rest, while the earth revolved round 
the sun, and also turned round every day. This 
system is called the Copernican System, and some- 
times the Solar System. 

Copernicus knew that few would believe that 
the earth moved while the sun stood still, and 
for some years taught his system only to his 
friends. At length he permitted his book to be 
published. But the very day it was to come 
from the press, he was taken very sick. As he 
lay upon his couch, with his disciples around him, 
a friend entered the room with the first printed 



134 ASTRONOMY. 

copy of the work. Copernicus bid him place it 
before the window, where the light might fall 
upon it. He did so. Copernicus turned his 
eyes to behold it — took it in his arms — pressed it 
to his bosom, and soon after died. 

Galileo, an Italian, was the first who surveyed 
the heavens with a telescope. Turning this in- 
strument to the sky, he beheld mountains and 
valleys on the moon, Venus exhibiting phases, a 
ring around Saturn, four moons revolving round 
Jupiter — things which no mortal eye had seen 
before. 

Galileo was convinced that the system of Co- 
pernicus was true, and taught that the earth 
moved. For this, at the age of seventy, he was 
summoned to Rome, and put in the dungeons of 
the Inquisition. 

After a time, he was brought before a court, 
composed of seven Cardinals. They condemned 
him to fall upon his knees, and solemnly to con- 
fess that the earth did not move. But as he rose 
from his knees, stamping on the floor, as if angry 
at what he had done, he declared, " But still it 
does move." For this he was again sent to 
prison. 

Of Tycho Brahe, Kepler, Newton, the Her- 
schels, and others, I cannot tell you now. — I 



HISTORY OF ASTRONOMY. 135 

trust, however, I have said enough to make you 
desirous of knowing more about this wonderful 
science. 

In this age, many skilful and patient eyes are 
ever watching the heavens to discover new won- 
ders. The telescope is ever busy with the sun, 
moon, and stars, to ascertain their nature, magni- 
tudes, motions, and distances. Those mysterious 
double stars, and those wonderful nebulae, are 
subjected to its untiring scrutiny. 

Within the last fifty years, more that two hun- 
dred asteroids, two satellites of Mars, and one 
more satellite of Saturn have been discovered. 
Most wonderful of all, the telescope has reached 
that far-off planet, Neptune, and added him, with 
his solitary moon, to the Solar System. 

Still there is no end. The science of Astro- 
nomy will ever continue to advance, and yet it 
will ever be true, that "these are but parts of 
the ways" of the Great Creator ! 



THE END. 



